2019/2020
Raquel Sofia da Silva Moreira
Hospitalizations for Varicella in children and adolescentes in Portugal:
2000 to 2015
Hospitalizações por Varicela em crianças e adolescentes em Portugal:
2000 a 2015
Mestrado Integrado em Medicina
Área: Pediatria
Tipologia: Dissertação
Trabalho efetuado sob a Orientação de:
Doutora Maria Inês Ferreira Águeda Azevedo
Trabalho organizado de acordo com as normas da revista:
International Journal of Infectious Diseases
Raquel Sofia da Silva Moreira
Hospitalizations for Varicella in children and adolesents in Portugal:
2000 to 2015
Hospitalizações por Varicela em crianças e adolescentes em Portugal:
2000 a 2015
“Matar o sonho é matarmo-nos. É mutilar a nossa alma. O sonho é
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por toda a ajuda e disponibilidade que sempre demonstraram
Um obrigada sincero a todos, por terem contribuído para que este sonho
esteja cada vez mais perto.
1
§Hospitalizations with Varicella in children and adolescents in
Portugal: 2000 to 2015
Raquel Sofia Moreira
1, José Fontoura Matias
2, Ana Reis Melo
2,3, Alberto Freitas
4,5, Inês
Azevedo
2,6,71
Faculty of Medicine, Universidade do Porto, Porto, Portugal
2
Department of Pediatrics, Centro Hospitalar São João, Porto, Portugal
3
Department of Biomedicine, Faculty of Medicine, Universidade do Porto, Porto,
Portugal
4
Department of Community Medicine, Information and Health Decision Sciences-
MEDCIDS, Faculty of Medicine, Universidade do Porto, Porto, Portugal
5
Center for Health Technology and Services Research (CINTESIS), Faculty of Medicine,
Universidade do Porto, Porto, Portugal
6
EpiUnit, Institute of Public Health, Universidade do Porto, Porto, Portugal
7
Department of Obstetrics, Gynecology and Pediatrics, Faculty of Medicine,
Universidade do Porto, Porto, Portugal
Correspondence: Inês Azevedo, Departamento de Ginecologia-Obstetrícia e Pediatria,
Faculdade de Medicina, Universidade do Porto, Alameda Professor Doutor Hernâni
Monteiro, Porto, 4200-319, Portugal. E-mail: iazevedo@med.up.pt
Declarations of interest: None
Funding: This research did not receive any specific grant from funding agencies in the
public, commercial, or not-for-profit sectors
2
Abstract
Objectives: Varicella is a common usually benign and auto-limited disease in children,
but can lead to severe complications and hospitalization. With this study, we aim to
analyze all varicella hospitalizations in order to provide epidemiological information to
help outlining preventive policies.
Design/Methods: We assessed all varicella hospitalizations in children from 0 to 17 years
of age, from 2000 to 2015, in mainland public Portuguese hospitals, using a Portuguese
administrative database. Seasonality, geographic distribution, severity, complications,
risk factors and use of diagnostic and treatment procedures were analyzed by age groups.
Results: A total of 5,120 hospitalizations were registered, with an annual rate of 17.2
hospitalizations/100,000 inhabitants. Higher number of hospitalizations occurred during
the summer period and in Southern regions. The median length of stay was of four days.
We found a high rate of severe, mostly dermatological, neurological and respiratory
complications. Of the total of patients, 0.8% were immunocompromised and 0.1% were
pregnant. Total direct hospitalization costs during the 16-year period were estimated to
be 7,110,718.70€.
Discussion: This study provides useful epidemiological data to evaluate the relevance of
including the Varicella Zoster Vaccine in our National Vaccination Program.
3
Introduction
Varicella is a common exanthematic disease, caused by Varicella Zoster Virus
(VZV) that represents a significant health burden. [1] In the absence of vaccination,
around 90% of varicella cases occur before 13 years of age, particularly in pre-school
children. [1] Despite being usually a benign and self-limited disease, varicella can lead to
severe complications requiring hospitalization.[2][3]
The main complications associated with varicella are skin and soft tissue
infections, including cellulitis and necrotizing fasciitis,[4] pneumonia, neurological
complications such as meningitis, encephalitis and ataxia, and sepsis.[5] The vaccine was
created as a strategy to prevent the infection by VZV, and its complications.[6][2]
Vaccination policies vary among countries, depending on local resources to reach and
sustain a vaccine coverage level of ≥80%, as recommended by the World Health
Organization. [7] In Portugal, the two life attenuated vaccines are available for
prescription since 2003 but are not yet included in the routine National Vaccination
Program, as thus only a small proportion of the children are vaccinated.
Up to our best knowledge, there is only one study analyzing the incidence of
hospitalizations for varicella in Portugal, using limited data from one hospital.[8] The
purpose of our study is to evaluate the hospitalizations related to varicella in children and
adolescents, in all the public Portuguese mainland hospitals, between 2000-2015, and
assess the main complications, severity and direct costs, in order to help to analyze the
potential benefit of the introduction of the varicella vaccine in the National Vaccination
Program.
4
Methods
Study Design
We conducted a retrospective observational study, including all patients who were
hospitalized from 2000 to 2015 with varicella, using the code 052.X from the
International Classification of Diseases, Ninth Revision, Clinical Modification
(ICD-9-CM). We used an administrative database from mainland public hospitals, supplied by
ACSS - Central Administration of the Health System, an agency that belongs to the
Portuguese National Health System and collects administrative and clinical information,
as diagnoses and procedures, through ICD-9-CM codification, related to all
hospitalizations. We considered only inpatient episodes, with a length of stay (LOS) of
one day (24 hours) or more, and a diagnosis of varicella at any stage.
Population data from 2000 to 2015 was considered as available on the National
Statistics Institute (Statistics Portugal - INE) website. [9]
Outcome Measures
The main outcomes were the number of hospitalizations with varicella and the rate
of admissions per age group. As secondary outcomes, we assessed the seasonality and
geographic distribution, severity, risk factors, use of diagnostic tests, required treatment
and direct costs.
Seasonality was assessed by month of hospitalization, and geographic area was
evaluated using the level II of the NUTS classification (Nomenclature of Territorial Units
for Statistics). [10]
Severity was evaluated by LOS, in-hospital mortality rate, use of invasive
(ICD-9-CM 96.70, 96.71, 96.72) or non-invasive ventilation (93.90) or of oxygen supply
(93.96) and by the main complications associated to varicella. These later were assessed
5
using ICD-9-CM codification (available at Table, Supplementary online material 1). The
risk factors considered were immunodeficiency (042, 279.X) and pregnancy (V22,
V23.83, 647.6). The diagnostic procedures analyzed were: chest x-ray (87.44, 87.49);
head CT scan (87.03); brain MRI (88.91); microscopic examination of the blood (90.5X).
As required treatments, we evaluated the use of intravenous antibiotics (00.14, 99.21,
99.22, E930.9, 960.X), intravenous fluid therapy (99.18), oxygen supply and mechanical
ventilation.
Direct costs were estimated using a budget allocation model based on
diagnosis-related groups (DRG), through the use of hospital reimbursement tables, provided by the
Portuguese Health Service and established by the Portuguese government. [11]
Data analysis and Statistical Analysis
The population was analyzed according to gender and age. Considering age, the
patients were divided into six groups: 0-28 days, 28 days-5 months, 6-11 months, 1-4
years, 5-9 years, and 10-17 years.
Descriptive analyses were carried out using using IBM SPSS Statistics 24 for Windows
and Microsoft EXCEL 2018. Frequencies and percentages were calculated taking in
account each age group. Continuous variables are presented as mean (SD) or median
(IQR, [P25; P75]), as apropriate. To calculate the rates, we used as denominator the
Population data provided by National Institute of Statistics
.Ethics
The dataset was previously anonymized and its use authorized by ACSS through a
protocol with CINTESIS/FMUP (Center for Health Technology and Services Research /
Faculty of Medicine of the University of Porto, Portugal).
6
Results
During this 16-year period, a total of 5,120 hospitalizations with varicella in
children, in mainland Portuguese public hospitals, were registered (Table 1), 3,645 of
them with Varicella as first stage of diagnose. The average number of hospitalizations
was 320 per year, providing an annual rate of hospitalization of 17.2/100,000 inhabitants.
Children between one and four years of age accounted for 58% of the total admissions;
4% occurred in newborns, 9% between 28 days and 5 months of age, 8% between 6 and
11 months of age, 16% between 5 and 9 years of age and 6% between 10 and 17 years of
age. There were two cases of congenital varicella registered. The age group between birth
and 28 days of age registered the higher admission rate, 148.2/100,000 inhabitants. (Table
1).
Males accounted for 54.7% of cases. There were four peaks of hospitalizations, in
2004, 2007, 2011 and 2014 (figure 1). The highest number of admissions occurred in
2007, with 475 admissions. The annual distribution by month showed a higher number of
cases between April and August, mostly during the warmer months (June, N=790 and
July, N=804) (figure 2). The rate of hospitalizations was higher in southern areas as
Alentejo (26.4) Lisbon (21.2) and Algarve (17.2), than in Center (16.7) and North (14.5)
regions.
The median LOS was 4 days [IQR 3-7]. The highest LOS was observed for
children between 0 and 28 days of age, with a median LOS of 7 days. The need for
mechanical ventilation was reported in 53 children, in 79% of them invasive ventilation.
Forty-nine children (0.9%) had the presence of a risk factor, immunodeficiency in 39, and
pregnancy in six.
7
The most requested diagnostic procedure was microscopic examination of the
blood (74.2%). Chest x-ray, head CT scan and brain MRI were requested in 26.3%, 4.9%
and 2.0%, respectively.
Intravenous antibiotics were prescribed in 61.8% of the patients and intravenous
fluid therapy in 47.4%. The main complications related to varicella are shown on Table
2. The most frequent were skin infections, as impetigo (10.7%), cellulitis (6.3%) and
necrotizing fasciitis (0.5 %), followed by respiratory and neurological disorders, mainly
pneumonia (4.4%) and encephalitis (3.6%).
There were eight deaths during this period (corresponding to 0.15% of the
admissions), three in children with acute lymphocytic leukemia, one with pneumococcal
septicemia, one with streptococcal septicemia, one with E. coli infection, one with
postinfectious intestinal adhesions with obstruction and one with complicated varicella
as a first diagnose.
The mean and median estimated costs directly related to the hospitalizations were
1,388.80€ and 560.0 € [560.0–1,355.8], respectively. Over the 16 years, the total costs
were estimated to be 7,110,718.70 €.
8
Discussion
This is the first study in Portugal accessing hospitalizations with varicella in
children and adolescents, in all mainland public Hospitals, and, therefore, important to
analyze the impact that varicella has in our country
.
During these sixteen years of study,
we registered a total of 5,120 hospitalizations, 3,645 which were admitted with a primary
diagnosis of varicella. These are the cases that most reliably portray hospitalizations for
complications directly related to varicella infection.
The rate of admissions longer than 24 hours was 17.3/100,000 inhabitants, which
is higher than reported in Denmark, England and Norway (11, 7.6 and 7.3,
respectively)[12][13][14] but lower when compared with data from Belgium and Spain
(29.5 and 23.6)[15][16]
The age group in which the rate of hospitalizations was higher was in newborns,
and progressively decreased as age advanced. This can be explained by the fact that
newborns have a significant risk of life-threatening complications in case of perinatal
infection and require greater attention and intravenous treatment.[17] As in Portugal
varicella is not a mandatory notifiable disease, we are unable to access the exact number
of cases for each age group, but it is predictable that the highest incidence rate of cases
occur in children between one and four years of age, as it is the age group in which most
children have their first contact with other children, in daycare centers and school, and
therefore in which there is greater risk of contagion, as it happens in other
countries.[13][16][18][19] This was shown in other countries in which varicella is a
mandatory notifiable disease.[20][21]
In this 16-year study, the number of admitted cases has varied unevenly. After the
introduction of the vaccine in the market, in 2003, the number of hospitalizations did not
show a decreasing pattern, with the highest peak of hospitalizations being recorded in
9
2007. This is probably due to a low varicella vaccine coverage in children, as according
to WHO recommendations, and national recommendations from the Pediatric Portuguese
Society, the vaccine is not recommended for healthy young children outside a National
Vaccination Schedule that can assure a high vaccine coverage. [7]
Most hospitalizations occurred between April and August, with a peak in June and July,
which is in agreement with data from Spain, which has weather conditions similar to our
country. [15]
Studies from Turkey, Poland and Sweden showed different results, with
most admissions occurring between December and March. [18][20][21]
Regarding geographic distribution, the region with the highest rate of admissions
was Alentejo, followed by Lisbon, Algarve, Center and North. The southern regions of
Portugal are the most sought areas during the summer months, when hospitalizations were
higher, which might explain why the highest proportion of cases has occurred in these
areas, but another plausible explanation could relate to a higher solar radiation in the
southern areas of Portugal, as Hervas et al suggested that solar radiation could be
important in the dynamics of varicella in Mallorca, Spain.[22]
The median LOS was four days (IQR 3 – 7), which is also consistent with data
from other studies.[12][15][19][23] It was similar for all age groups, with the interquartile
range being slightly higher at the extremes of age (0-28 days and 10-17 years). In the case
of newborns, it can be explained once again by the fact that newborns do not yet have a
well-developed immune system and so required increased vigilance from the healthcare
workers. On the other hand, complications tend to be more severe when the infection
occurs in adolescents, as it happens in adults which may justify the need for a longer
hospital stay. [7][24]
Complications were reported in 49.8% of cases, and as expected the most common
were dermatological, mainly impetigo, cellulitis and abscesses, but it important to notice
10
that necrotizing fasceiitis occurred in 0.5% of cases. Severe neurological complications
occurred in 4.4% of cases, noteworthily encephalitis, that was more commonly reported
in children older than 4 years. Respiratory complications, mainly pneumonia, were
reported in 5.1% of children and life-threatening complications such as sepsis or acute
respiratory distress syndrome were reported in around 2% of the cases. This is consistent
with other studies, in which dermatological, neurological and respiratory complications
are the three most commonly complications associated with varicella, although the
incidence for each one varies from country to country.[4][12][15][16][18][19] This can
be explained by the susceptibility of individuals for specific diseases, and other yet not
totally understood differences such as climatic factors and population density.
We were not able to directly assess the number of ICU admissions and, therefore,
we used the need for mechanical ventilation, either invasive or non-invasive, to estimate
these admissions. Around 1% of hospitalized children required mechanical ventilation,
0.8% of them non-invasive ventilation.[25]
A total of eight deaths (0.2%) were registered
during this period, consistent with the percentage found in other European
countries.[12][14][16][18] This number shows that despite being commonly a benign
disease, varicella can lead to some serious and fatal complications, especially when it
occurs in at risk patients, as happened in our cases. There were 0.8% of cases associated
with immunosuppression and 0.1% (six cases) in pregnancy. The proportion o f
hospitalized immunocompromised individuals was lower than found in other
studies.[12][16][19] These cases were identified selecting the ICD-9-CM codes related to
immunosuppression only (ICD-9-CM 0.42 and 279.X), which may explain the
differences found. There are many other conditions that may not be codified and that can
lead to immunocompromised states, that were not accounted for. This leads to an
underestimation of the percentage of hospitalized immunocompromised children. The
11
importance of pregnancy as a risk factor is not only related to the consequences that it can
bring to the mother, but was considered specially to assess the risk of congenital varicella,
which can lead to very severe and fatal complications for the baby.
The mean direct cost related to the hospitalizations was around 1,388.80€, which
is less than compared with Spain and England, where the costs are around 3,933.80€ and
2,037.64 € per patient, respectively. [13][26][27] It would be interesting to make a more
realistic approximation of costs in a future study, as it was made in Hungary.[23] It is
important to bear in mind that the full financial burden related to varicella hospitalizations
is grossly underestimated, as they take only in account the values established by the
Ministry of Health for reimbursement, according to the diagnosed-related group in
question and other costs related to parents’ days missed from work and the follow-up of
patients nor the burden of sequalae were not considered.
Our findings showed that varicella is responsible for a considerable number of
hospitalizations in our country. However, there are some limitations in our study that must
be considered. Firstly, as referred, varicella is not a mandatory notifiable disease, which
means that we cannot estimate a real rate between hospitalizations and children infected
with varicella, as done in other countries. [28][29][30] Also, it is important to be aware
that in a percentage of cases, that we cannot calculate accurately, the hospital admission
may have occurred for another reason, regardless the concomitant diagnosis of varicella,
which may end up overestimating the results. We used the ICD-9-CM codification to
identify varicella cases, yet, it is possible that the codification is not as accurate as we
intended, and it can lead to an underestimation of the incidence of hospitalizations. In
addition, the clinical record itself may not be done in the most correct way by health
professionals, leading to codification failures and, consequently, lack of information.
Even when it comes to complications, they may be underestimated, considering, in many
12
cases, that only a single code is attributed as diagnosis to a patient. On the other hand, it
can happen that only the complication associated with varicella is coded, without coding
varicella itself.
Regarding the calculation of rates, we used data from the National
Institute of Statistics. However, for the first year of life, there is no breakdown of the
population for each month of life and, as such, in the case of age groups between 0-28
days, 28 days- 5 months and 6-11 months, the population was estimated assuming a
similar distribution over the months of age, which makes the rates calculated for these
age groups an approximation of reality.
In Portugal, even though the vaccine is available since 2003, it is not part of the
National Vaccination Program. We could not access the real number of vaccinated
children, and for that reason we have not been able to reliably compare the pattern of
hospitalizations between vaccinated and unvaccinated children, as has already been done
in other countries. [31][32][33][34][35][36][37][38]
With this study, we believe we have provided important epidemiological
information on varicella admissions in mainland Portuguese hospitals, which could be
useful for considering varicella universal vaccination in the future.
Acknowledgements
The authors would like to thank the Portuguese Ministry of Health for providing
access to the hospitalization data managed by the Portuguese Central Health System
Administration (Administração Central do Sistema de Saúde).
13
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[37] Neyro SE, D M, Ferolla FM, D M, Molise C, D M. Impacto clínico y
epidemiológico de las infecciones por varicela en niños previo a la introducción de
la vacuna al Calendario Nacional de Argentina. Arch Argent Pediatr 2019;117:12–
8. https://doi.org/10.5546/aap.2019.12.
[38] Hagemann C, Krämer A, Grote V, Liese JG, Streng A. Specific Varicella-Related
Complications and Their Decrease in Hospitalized Children after the Introduction
of General Varicella Vaccination: Results from a Multicenter Pediatric Hospital
Surveillance Study in Bavaria (Germany). Infect Dis Ther 2019;8:597–611.
https://doi.org/10.1007/s40121-019-00273-6.
18
19
0- 28 days 28 days - 5 months 6- 11 months 1- 4 years 5- 9 years 10-17 years Total
Total Hospitalizations, N (%) 189 (4) 443 (9) 411 (8) 2,948 (58) 824 (16) 305 (6) 5,120
Hospitalization Rate (per 100,000) 148.2 69.5 53.7 46.8 10.2 2.24 17.3 Severity
LOS, median [IQR] 7 [5-9] 5 [3-7] 4 [3-6] 4 [2-6] 4 [2-7] 5 [3-8] 4 [3-7]
Mortality , N (%) 0 1 (0.22) 0 4 (0.14) 2 (0.14) 1 (0.33) 8 (0.15)
Mechanical Ventilation, N(%) 8 (4.2) 4 (0.9) 7 (1.7) 20 (0.7) 9 (1.1) 5 (1.6) 53 (1.0)
Invasive Ventilation , N (%) 3 (1.6) 0 1 (0.2) 4 (0.1) 1 (0.1) 2 (0.6) 11 (0.2)
Non- Invasive Ventilation , N (%) 5 (2.6) 4 (0.9) 6 (1.5) 16 (0.5) 8 (1.0) 3 (1.0) 42 (0.8)
Risk Groups Immunodeficiency, N (%) 1 (0.5) 2 (0.5) 1 (0.2) 17 (0.6) 12 (1.5) 6 (2.0) 39 (0.8) Pregnancy, N (%) 0 0 0 0 0 6 (2.0) 6 (0.1) DiagnosticProcedures ChestX-ray, N (%) 16 (8.5) 109 (24.6) 145 (34.5) 831 (28.2) 169 (20.5) 77 (25.2) 1,347 (26.3) Head CT scan, N(%) 1 (0.5) 6 (1.4) 9 (2.2) 126 (4.3) 78 (9.5) 30 (9.8) 250 (4.9) Brain MRI, N(%) 1 (0.5) 4 (0.5) 4 (1.0) 51 (1.7) 29 (3.5) 12 (3.9) 101 (2.0)
Microscopic examination of the blood, N
(%) 125 (66.1) 305 (68.8) 309 (75.2) 2,258 (76.6) 600 (72.8) 202 (66.2) 3,799 (74.2)
Required treatment
Intravenous antibiotics, N (%) 92 (48.7) 210 (47.4) 262 (63.7) 1,962 (66.6) 475 (57.6) 163 (53.4) 3,164 (61.8) Fluid therapy, N (%) 46 (24.3) 171 (38.6) 210 (51.1) 1,441 (48.9) 416 (50.5) 141 (46.2) 2,425 (47.4) Oxygen supply, N (%) 5 (2.6) 23 (5.2) 34 (8.3) 130 (4.4) 20 (2.4) 6 (2.0) 218 (4.3)
Table 1 - Characteristics of hospitalizations due to varicella in pediatric patients from 2000 to 2015, in mainland Portugal, by age groups
20 Figure 1 - Annual variation of Varicella-related hospitalizations, from 2000 to 2015, for each age group
2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 0 50 100 150 200 250 300 Year N um b er o f H o spi ta li z a ti o n s
21 Figure 2: Monthly variation of Varicella-related hospitalizations, from 2000 to 2015, for each age group
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
0 100 200 300 400 500 600 700 800 900 Month Cum ul a ti v e n um b er o f h o spi ta li z at io n s
22
0- 28 days 28 days - 5 months 6- 11 months 1- 4 years 5- 9 years 10-17 years Total
Skin Complications, N (%) 7 (3.7) 44 (9.9) 95 (23.1) 690 (23.4) 130 (15.8) 34 (11.1) 1000 (19.6) Abcess 0 2 (0.5) 10 (2.4) 76 (2.6) 11 (1.3) 4 (1.3) 103 (2.0) Cellulitis 0 14 (3.2) 29 (7.1) 228 (7.7) 39 (4.7) 12 (3.9) 322 (6.3) Necrotizing fasceiitis 0 0 2 (0.5) 18 (0.6) 7 (0.8) 0 27 (0.5) Impetigo 7 (3.7) 28 (6.3) 54 (13.1) 368 (1.2) 73 (8.9) 18 (5.9) 548 (10.7) Neurological Complications, N (%) 0 (0) 3 (0.7) 10 (2.4) 173 (5.9) 91 (11.0) 28 (9.2) 305 (6.0) Myelitis 0 0 0 1 (0.0) 5 (0.6) 0 6 (0.1) Encephalitis 0 2 (0.5) 2 (0.5) 93 (3.2) 69 (8.4) 19 (6.2) 185 (3.6) Meningitis 0 0 0 1 (0.0) 1 (0.1) 1 (0.3) 3 (0.1) Cerebellar Ataxia 0 0 0 11 (0.4) 7 (0.8) 4 (1.3) 22 (0.4) Febrile seizures 0 1 (0.2) 8 (1.9) 67 (2.3) 9 (1.1) 4 (1.3) 89 (1.7) Respiratory Complications, N (%) 3 (1.6) 13 (2.9) 27 (6.6) 168 (5.7) 40 (4.9) 10 (3.3) 261 (5.1) Acute tonsillitis 0 1 (0.2) 1 (0.2) 26 (0.9) 8 (1.0) 1 (0.3) 37 (0.7) Pneumonia 3 (1.6) 12 (2.7) 26 (6.3) 142 (4.8) 32 (3.9) 9 (3.0) 224 (4.4) Osteomuscular Complications, N(%) 0 (0) 0 (0) 9 (2.2) 47 (1.6) 16 (1.9) 2 (0.7) 68 (1.3) Mastoiditis 0 0 1 (0.2) 9 (0.3) 2 (0.2) 1 (0.3) 13 (0.3) Assseptic Arthritis 0 0 7 (1.7) 31 (1.1) 12 (1.5) 0 50 (1.0) Osteomyelitis 0 0 1 (0.2) 7 (0.2) 2 (0.2) 1 (0.3) 11 (0.2) Gastrointestinal Complications, N(%) 0 (0) 6 (1.4) 10 (2.4) 42 (1.4) 8 (1.0) 2 (0.7) 68 (1.3) Gastroenteritis 0 6 (1.4) 10 (2.4) 42 (1.4) 8 (1.0) 2 (0.7) 68 (1.3) Hematological Complications, N(%) 2 (1.1) 10 (2.3) 3 (0.7) 40 (1.4) 10 (1.2) 10 (3.3) 75 (1.5) Thrombocytopenia 0 0 0 4 (0.1) 1 (0.1) 1 (0.3) 6 (0.1) Neutropenia 2 (1.1) 10 (2.3) 3 (0.7) 36 (1.2) 9 (1.1) 9 (3.0) 69 (1.3) Infectious, other N(%) 6 (3.2) 13 (2.9) 19 (4.6) 73 (2.5) 21 (2.5) 2 (0.7) 134 (2.6) Sepsis 5 (2.6) 7 (1.6) 13 (3.2) 34 (1.2) 12 (1.5) 1 (0.3) 72 (1.4) ARDS 0 2 (0.5) 1 (0.2) 12 (0.4) 3 (0.4) 1 (0.3) 19 (0.4) Hyponatremia 1 (0.5) 4 (0.9) 5 (1.2) 27 (0.9) 6 (0.7) 0 43 (0.8) Congenital Varicella, N(%) 2 (1.1) 0 0 0 0 0 2 (0.04)
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INTERNATIONAL JOURNAL OF INFECTIOUS
DISEASES
Official Publication of the International Society for Infectious Diseases
AUTHOR INFORMATION PACK
TABLE OF CONTENTS
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.• Description
• Impact Factor
• Abstracting and Indexing
• Editorial Board
• Guide for Authors
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ISSN: 1201-9712DESCRIPTION
.The International Journal of Infectious Diseases (IJID) is published monthly by the International Society for Infectious Diseases. IJID is a peer-reviewed, open access journal and publishes original clinical and laboratory-based research, together with reports of clinical trials, reviews, and some case reports dealing with the epidemiology, clinical diagnosis, treatment, and control of infectious diseases with particular emphasis placed on those diseases that are most common in under-resourced countries.
IMPACT FACTOR
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2018: 3.538 © Clarivate Analytics Journal Citation Reports 2019
ABSTRACTING AND INDEXING
.
Directory of Open Access Journals (DOAJ)
EDITORIAL BOARD
.
Editor-in-Chief
Eskild Petersen, Aarhus University Hospital Institute of Clinical Medicine Department of Infectious Diseases, Skejbygaardsvej 100, 8200, Aarhus, Denmark
Editors
Lucille Blumberg, National Institute for Communicable Diseases, South Africa
Shui Shan Lee, Chinese University of Hong Kong Stanley Ho Centre for Emerging Infectious Diseases, /F Postgraduate Educ Centre,Prince of Wales Hospit, Hong Kong, Hong Kong
Ira Praharaj, Christian Medical College Vellore, 632004, Vellore, India
Sean Wasserman, University of Cape Town Institute of Infectious Disease and Molecular Medicine, Observatory 7925, Cape Town, South Africa
Editorial Office
Isabela Caus
Editorial Advisory Board
AUTHOR INFORMATION PACK 19 Apr 2020 www.elsevier.com/locate/ijid 2 Ashish Bhalla, Chandigarh, India
Bin Cao, Beijing, China
Ron Dagan, Be'er Sheva, Israel
David Fisman, Toronto, Ontario, Canada Rodrigo Guabiraba, Nouzilly, France Hajjeh, Egypt
Mark Holodniy, Stanford, California, United States Yao Kaihu, Beijing, China
Keith Klugman, Atlanta, Georgia, United States Hakan Leblebicioglu, Samsun, Turkey
Marc Mendelson, Cape Town, South Africa Xavier Sáez-Llorens, Panama City, Panama
Program Coordinator
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GUIDE FOR AUTHORS
.
Your Paper Your Way
We now differentiate between the requirements for new and revised submissions. You may choose to submit your manuscript as a single Word or PDF file to be used in the refereeing process. Only when your paper is at the revision stage, will you be requested to put your paper in to a 'correct format' for acceptance and provide the items required for the publication of your article.
To find out more, please visit the Preparation section below.
The International Journal of Infectious Diseases(IJID) is published monthly by the International Society for Infectious Diseases.
IJID is a peer-reviewed, open access journal and publishes position papers, original clinical and
laboratory-based research, together with reports of clinical trials, reviews, exceptional case reports. The interest areas of the IJID are epidemiology, clinical diagnosis, treatment, and control of infectious diseases with particular emphasis placed on under-resourced countries. The IJID does not publish veterinary studies and studies based on animal models alone.
Manuscript types
Original articles on infectious disease topics of broad interest. We particularly welcome papers that
discuss epidemiological aspects of international health, clinical reports, clinical trials and reports of laboratory investigations. Original articles should not exceed 3500 words in length.The word count is from the introduction through to the end of the conclusion/discussion and does not include abstract, tables, figures, acknowledgements or reference list.
Reviews on topics of importance to readers in diverse geographic areas. These should be
comprehensive and fully referenced.
Article requirements: Word count for the main part of the manuscript from introduction to conclusion/ discussion: 2,500 to max of 4000 words. One or two figures/tables, a brief abstract, an introduction, a conclusion, and no more than 30 references.
Perspectives are papers that advance a hypothesis or represent an opinion relating to a topic of
current interest or importance. They should be fully referenced, and should not exceed 2000 words in length.
Correspondence relating to papers recently published in the Journal, or containing brief reports of
unusual or preliminary findings. Maximum length 400 words, one table or figure and a maximum of 10 references.
Case Reports must be carefully documented and must be of importance because they illustrate or
describe unusual features or have important therapeutic implications. Maximum length 1200 words and a maximum of 1 table or figure. Case reports require an abstract, but this does not need to be a structured abstract and should include no more than 15 references.
Short Communications brief reports of unusual or preliminary findings. Maximum length 800 words,
two tables or figures and a maximum of 10 references.
Medical Imagery: We would like to invite submission of high-quality, interesting and instructive
images (such as clinical and other photographs, figures or diagrams, photomicrographs, or diagnostic imaging) suitable for the general readership of IJID. These should include no more than 200 words of explanatory text, and under 5 references. It is necessary to have appropriate permissions from subjects for an identifiable clinical image to be published.
Contact details
If you have any problem submitting your paper online please contact Annette Fowler at IJID@elsevier.com
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PREPARATION Peer review
This journal operates a single blind review process. All contributions will be initially assessed by the editor for suitability for the journal. Papers deemed suitable are then typically sent to a minimum of two independent expert reviewers to assess the scientific quality of the paper. The Editor is responsible for the final decision regarding acceptance or rejection of articles. The Editor's decision is final. More information on types of peer review.
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Authors are encouraged to check accession numbers used very carefully. An error in a letter or
number can result in a dead link. In the final version of the printed article, the accession number
text will not appear bold or underlined. In the final version of the electronic copy, the accession number text will be linked to the appropriate source in the NCBI databases enabling readers to go directly to that source from the article.
Acknowledgements
Collate acknowledgements in a separate section at the end of the article before the references and do not, therefore, include them on the title page, as a footnote to the title or otherwise. List here those individuals who provided help during the research (e.g., providing language help, writing assistance or proof reading the article, etc.).
Formatting of funding sources
List funding sources in this standard way to facilitate compliance to funder's requirements:
Funding: This work was supported by the National Institutes of Health [grant numbers xxxx, yyyy]; the Bill & Melinda Gates Foundation, Seattle, WA [grant number zzzz]; and the United States Institutes of Peace [grant number aaaa].
It is not necessary to include detailed descriptions on the program or type of grants and awards. When funding is from a block grant or other resources available to a university, college, or other research institution, submit the name of the institute or organization that provided the funding.
If no funding has been provided for the research, please include the following sentence:
This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.
Embedded math equations
If you are submitting an article prepared with Microsoft Word containing embedded math equations then please read this (related support information).
Artwork
Electronic artwork General points
• Make sure you use uniform lettering and sizing of your original artwork. • Embed the used fonts if the application provides that option.
• Aim to use the following fonts in your illustrations: Arial, Courier, Times New Roman, Symbol, or use fonts that look similar.
• Number the illustrations according to their sequence in the text. • Use a logical naming convention for your artwork files.
• Provide captions to illustrations separately.
• Size the illustrations close to the desired dimensions of the published version. • Submit each illustration as a separate file.
• Ensure that color images are accessible to all, including those with impaired color vision. A detailed guide on electronic artwork is available.
You are urged to visit this site; some excerpts from the detailed information are given here.
Formats
If your electronic artwork is created in a Microsoft Office application (Word, PowerPoint, Excel) then please supply 'as is' in the native document format.
Regardless of the application used other than Microsoft Office, when your electronic artwork is finalized, please 'Save as' or convert the images to one of the following formats (note the resolution requirements for line drawings, halftones, and line/halftone combinations given below):
EPS (or PDF): Vector drawings, embed all used fonts.
TIFF (or JPEG): Color or grayscale photographs (halftones), keep to a minimum of 300 dpi.
