Diseases Subject to the International Health
Regulations
Cholera, yellow fever, and plague cases and deaths reported
in the Region of the Americas up to 15 October 1980
Country and Yellow fever
administrative Cholera Plague
subdivision Cases Cases Deaths Cases
BOLIVIA - 46 39 15
Cochabamba - 12 8
-La Paz - 32 30 15
Santa Cruz - 1 1
-Tarija - 1
-BRAZIL - 25 22 69
Ceará - - - 62
Goiás - 20 19
Maranhao - 4 2
-Pernambuco - - - 7
Rondónia - 1 1
-CANADA 3 - -
-Quebec 1 -
-Saskatchewan 2 -
-COLOMBIA - 7 7
-Cesar - 1 1
-Guaviare - 1 1
-Meta - 1 1
-Norte de Santander - 1 1
-Putumayo - 3 3
-ECUADOR - 2
-Napo - 2
PERU - 24 19
-Ayacucho - 8 7
-Junín - 7 4
-San Martín - 7 7
-...
- 2 1
-UNITED STATES 8 - - 13
California 6 - 2
Maryland 1
-Nevada - - - 2
New Mexico - - - 9
Pennsylvania 1 -
-VENEZUELA - 1 1
-Mérida - 1 1
-None.
... Data not available.
Accidental Smallpox Vaccination in Venezuela
On 31 July 1980 a report was received that the previous day a 10-month old child weighing 10 kg, who had been taken for measles vaccination in Barquisimeto, Lara State, had accidentally received in the left arm a sub-cutaneous injection of 25 doses of freeze-dried smallpox
vaccine (lot No. 48 produced by the National Institute of Health), rehydrated in the diluent of the Merieux Lab-oratory measles vaccine. In a way, the accident provided an opportunity for reinforcing the principle that those in charge of programs should supervise the immunizations
5
more closely. It also provided an example of what can happen, and the state epidemiologists who were attend-ing a course on cold chain at the time in the Epidemiology Division, in Caracas, were informed of the incident.
The smallpox vaccine used by mistake had been shipped in 1978 by the National Storage Facility to Bar-quisimeto, where it had been kept under refrigeration (+40 to 80C) for two years. Once the error was dis-covered, the child was placed under close observation and treated with methisazone (Marboran), and on 31 July and 1 August received a total of 0.9 g orally.
The child felt no discomfort until 3 August (4th day following vaccination), when he registered a fever of 38.5°C, and a papule, 2 cm in diameter and a hardened center appeared; there was no axillary adenitis or change in his general condition. On 4 August (5th day following inoculation), the child was examined by a physician of the Epidemiology Division, and on that occasion was given 6 ml of antivaccinia gamma globulin of human ori-gin, of which 1 ml was infiltrated around the lesion and 5 ml was administered intramuscularly. This material was provided by the United States Armed Forces through the Center for Disease Control, and was obtained through the prompt intervention of PAHO (the Caracas and Washington offices).
On 7 August (8th day after inoculation), the lesion re-turned to normal size and the hardening and fever dis-appeared. On 11 August (12th day after inoculation) the child recovered completely.
Editorial Comment
In the case reported, the nurse thought she had pre-pared measles vaccine, which could be explained by the fact that there is some outward resemblance between the containers of smallpox and measles vaccines. When pre-pared with the measles vaccine diluent, however, the smallpox vaccine is transparent, in distinct contrast to the pinkish tint of the measles vaccine itself. In fact, it was the lack of color in the unused portion of the vaccine prepared that made the nurse realize the mistake. Moreover, the methisazone treatment was insufficient, since the recommended dosage for preventing postvac-cination lesions from measles vaccine is 80 mg per kg of body weight (the patient should have been given 8 g and not 0.9 g).
This accident calls attention once again to the need to keep vaccines in the refrigerators of local health services clearly identified and arranged, to ensure that the vac-cine administered is the right one. Priority should be given to these practical aspects in the training of vac-cination personnel, particularly since the containers of typhoid, DPT, and tetanus toxoid vaccines are identical.
The fact that smallpox vaccine was administered at all prompts yet another important comment. Since this dis-ease has been officially eradicated throughout the world, one would wonder why Venezuela and other countries continue to vaccinate against it. It will be recalled that the last outbreak of alastrim occurred in May-April 1962, when the National Institute of Health (INH) confirmed 11 cases among the Pemone Indians of the Great Savanna, in Bolívar State (on the Venezuelan-Brazilian border). The last cases of smallpox in the Hemisphere were reported in April 1971 in Guanabara, Brazil, 400 years after its introduction into the New World.
In 1967 WHO launched the worldwide campaign for the eradication of smallpox, and a decade later an-nounced that the last case of endemic smallpox had been recorded in Somalia in October 1977.
On 25 January 1980 WHO proclaimed that the eradi-cation of smallpox throughout the world had been achieved, and stated that there was no reason to fear a recurrence of the disease. On that date it also approved the following recommendations:
1. That smallpox vaccination be discontinued in all countries except in the case of research workers at special risk.
2. That the vaccination requirement for international travel be lifted.
3. That 200 million doses of freeze-dried smallpox vaccine be kept in storage in two countries.
4. That some high-security laboratories be permitted to preserve and keep smallpox virus.
Worthy of mention is the fact that Venezuela has not yet changed its Vaccination Law (1912) or its Regula-tions (1921), which make smallpox vaccination com-pulsory and lay down the standards for schoolchildren, the Armed Forces, and international travelers. For the last three years the Epidemiology Division has been de-creasing the number of vaccinations, and the INH has produced no vaccine since 1977; however, the INH keeps 7 kg of freeze-dried calf pulp, the equivalent of some 2 million doses.
Table 1 shows the vaccinations performed from 1968 to 1979 and the number of postvaccination deaths (en-cephalitis in children undergoing primary vaccination). As early as 1966 the Epidemiology Division had esti-mated a frequency of one case of encephalitis for every 120,000 primary vaccinations in individuals at least five years old, with a letality rate of 25 per cent. Fortunately, the case described in this report had a happy outcome, but it does call attention to the urgency of strict com-pliance with WHO recommendations.
Finally, the National Health Department, the Epi-demiology Division, and the Legal Counsel of the
Minis-6
.
Table 1. Smallpox vaccination and deaths from postvaccina-tion reacpostvaccina-tion, Venezuela, 1968-1979.
Vaccinations (in thousands of doses)
Revaccina-Year Total Primary tions Deaths
1968 1,592.8 663.7 929.1 1
1969 1,378.7 598.1 780.6
-1970 1,119.2 890.1 229.1 3
1971 870.0 630.6 239.4 2
1972 786.0 568.1 217.9 2
1973 691.7 480.0 211.7
-1974 617.9 385.8 232.1
-1975 526.2 311.3 214.9 1
1976 429.1 202.9 226.2
-1977 387.0 177.1 209.9
-1978 133.0 68.1 64.9
-1979 66.6 ...
-Source: Morbidity Section, Epidemiology Division, Ministry of Health and Social Welfare.)
try of Health and Social Welfare and studying the legal basis for amending the Vaccination Law in order to estab-lish a policy in keeping with the WHO recommendations.
(Source: Boletín Epidemiológico Semanal
No. 32, 3-9 August 1980. Division of Epidemiology, Ministry of Health and Social Welfare, Venezuela.)
Argentinian Hemorrhagic Fever
Argentinian hemorrhagic fever (AHF) is an endemo-epidemic anthropozoonosis that has gradually spread in the pampas of Argentina, as shown in Figure 1.
The etiologic agent of AHF is the Junín virus, one of the four arenaviruses that are pathogenic for man, the other three being the virus of lymphocytic choriomen-ingitis (LCM), that of Lassa fever, and the Machupo virus, which causes Bolivian hemorrhagic fever.
With the exception of the Lassa fever virus and the Tamiami virus, all the other arenaviruses are found in different geographic areas of Latin America. These viruses are associated with different rodent species in which they produce persistent infections that ensure their maintenance in nature. Each of these agents is found in autochthonous rodents of geographic regions that are usually far removed from one another. However, in the AHF endemic region, the simultaneous activity of two arenaviruses pathogenic for man-the Junín and the LCM-has been confirmed.
This report covers various statistical aspects of the AHF, the results of recent studies that will contribute to the diagnosis and treatment of this disease, and an ac-count of research for the development of a vaccine.
Figure 2 shows the total number of cases reported
an-nually with a presumptive clinical diagnosis of AHF since 1958, when official records of this disease were begun.
Table 1 shows the distribution of the cases studied in Pergamino since 1965. As may be seen, an etiologic diagnosis of AHF was established in approximately 70 per cent of the cases reported in Pergamino in that 15-year period. Most of the remaining 30 per cent of the cases reported on the basis of a clinical diagnosis of AHF were patients who possibly suffered from virus infections of a different etiology.
Table 2 shows the distribution by sex and age group of the cases with an etiologic diagnosis of AHF that were studied in Pergamino. The marked predominance of males and of middle-aged persons is evident.
Table 3 shows the results of a controlled therapeutic study, which clearly demonstrates the effectiveness of im-mune plasma in reducing AHF case-fatality ratio if it is administered within eight days of onset of the disease. This study showed that immune plasma acts by neutral-izing the viremia of the acute period of AHF. These re-sults show that, for the treatment of AHF patients, it is essential to use plasma units containing specific Junín antibodies. So far, this has not been possible for two main reasons: first, because in som.e medical care
