Skip Navigation LinksSkip Navigation Links
Centers for Disease Control and Prevention
Safer Healthier People
Blue White
Blue White
bottom curve
CDC Home Search Health Topics A-Z spacer spacer
Blue curve MMWR spacer

Post-Smallpox Eradication Surveillance

In conformity with the 1980 recommendations of the Thirty-third World Health Assembly for post-smallpox eradication surveillance, the World Health Organization (WHO) is continuing to coordinate and participate in the investigation of suspected smallpox cases throughout the world.

Since January 1979, 143 reports of suspected smallpox have been received from 58 countries--15 of them during the last 12 months. These reports were investigated by national health authorities or joint national/WHO teams, and when required, specimens were collected and tested by a WHO collaborating center for laboratory confirmation of diagnosis. Results of the investigation of 142 reports (one is still under investigation) showed that none was smallpox; they were actually misdiagnosed cases of chickenpox, measles, or diseases other than smallpox. These results further augment confidence in the absence of smallpox worldwide. NIGERIA

The results of investigation of an outbreak of fever and rash disease reported by the press as smallpox are presented below. This is one example of a smallpox report that received international attention and was clarified through the joint efforts of WHO and the government concerned.

On November 19, 1982, a Nigerian newspaper published an article describing an outbreak of suspected smallpox with more than 17 cases that occurred in Onitsha prison in Anambra State. On November 23, the National WHO Program Coordinator in Lagos, Nigeria, brought this report to the attention of the national health authorities. By the middle of December 1982, the outbreak had already been investigated by a medical officer in Onitsha and a diagnosis of chickenpox made.

Meanwhile, the outbreak continued, and the report received international attention. In December, WHO was asked by scientists from the Federal Republic of Germany and the United States to clarify this report. At the request of the Smallpox Eradication Unit, WHO, the national health authorities further investigated the outbreak and collected specimens that were dispatched for testing at a WHO collaborating laboratory. The results of these investigations follow:

During January 23-26, 1983, a team from the Federal Epidemiological Division of the Ministry of Health headed by the Principal Health Superintendent with the participation of medical personnel of the Onitsha local government area visited the prison to investigate the outbreak, and confirmed the diagnosis of chickenpox.

The first cases occurred at the beginning of November, and by November 19, they totaled 20. From the outset, the outbreak was monitored by the Medical Officer of Health responsible for the Onitsha local government area. By November 30, there were 79 cases, and by December 14, 120 cases of chickenpox had been recorded. When the team from the Federal Epidemiological Division arrived at the end of January to carry out the investigation, the outbreak was still continuing, and four cases in the acute stage of the disease were noted.

Results of clinical examination showed that the distribution of rash, the stage of its development, the absence of lesions on the palms and soles, and other signs conformed with a diagnosis of chickenpox. Nevertheless, skin lesion specimens were taken from two of the patients, and some convalescent serum specimens were also collected from other persons. All these specimens were promptly sent to the WHO Collaborating Center for Poxvirus Diagnosis and Research at the Centers for Disease Control (CDC), Atlanta, Georgia, and the laboratory results were made available within a few days. The laboratory examination revealed herpes varicella particles in skin lesion specimens, thus confirming the clinical diagnosis of chickenpox. The results of the investigation were communicated to those persons in the Federal Republic of Germany and the United States who had requested WHO to clarify this report. INDIA

At the beginning of June 1983, a daily newspaper in Patna (Bihar, India) published a photograph of a young girl with facial skin lesions. The case was diagnosed as chickenpox by local physicians. However, the newspaper caption read, "Smallpox, the dreaded disease, which was supposedly eradicated from Asia, has struck again in Patna." The photograph and comments were later reprinted in newspapers in other Indian States, as well as abroad. The report created concern, and WHO was asked by the members of the media whether or not the report was correct.

The Union Ministry of Health (New Delhi) sent officials with smallpox experience from the National Institute of Communicable Disease (New Delhi) to carry out an independent "on-the-spot" investigation. The patient, a 12-year-old girl, was located and examined. She had a scar indicating a successful vaccination against smallpox. Clinical and epidemiologic examination confirmed the diagnosis of chickenpox. Further skin samples were collected and sent to the National Smallpox Reference Laboratory, Delhi, and to the WHO Collaborating Center at CDC. No viruses belonging to the orthopoxvirus group were identified by these laboratory examinations. Reported by WHO Weekly Epidemiological Record, 1983:58;226-7.

Disclaimer   All MMWR HTML documents published before January 1993 are electronic conversions from ASCII text into HTML. This conversion may have resulted in character translation or format errors in the HTML version. Users should not rely on this HTML document, but are referred to the original MMWR paper copy for the official text, figures, and tables. An original paper copy of this issue can be obtained from the Superintendent of Documents, U.S. Government Printing Office (GPO), Washington, DC 20402-9371; telephone: (202) 512-1800. Contact GPO for current prices.

**Questions or messages regarding errors in formatting should be addressed to

Page converted: 08/05/98


Safer, Healthier People

Morbidity and Mortality Weekly Report
Centers for Disease Control and Prevention
1600 Clifton Rd, MailStop E-90, Atlanta, GA 30333, U.S.A


Department of Health
and Human Services

This page last reviewed 5/2/01