Contact tracing based on the first case of monkeypox to be identified in South Africa is currently underway. The National Institute of Communicable Diseases (NICD) was notified of a potential case via its hotline on Monday, June 20, said Nevashan Govender, head of the NICD’s emergency operations center.
On Wednesday, lab tests confirmed the case to be monkeypox.
“Unfortunately, because there is no travel history for this particular case, it means the disease was acquired locally. So… the case-finding process is ongoing,” said Dr. Jacqueline Weyer, senior medical scientist at NICD.
“The idea is to identify the contact the individual had, in the time period that would make sense for when we would expect them to have contracted the disease.”
read in Daily Maverick: First case of monkeypox confirmed in South Africa
Govender and Weyer were speaking Thursday at a press briefing hosted by the NICD. Weyer pointed out that because monkeypox tends to move quite slowly through a population, it should be possible for the NICD to identify those who have come into contact with the disease and the resulting chains of transmission.
The NICD was consulting with World Health Organization recommendations on disease containment and had already adopted standard operating procedures for screening and test monitoring, Weyer said. The NICD uses a classic containment approach, which involves:
- Put in place measures to increase sensitivity for case detection;
- Conduct contact tracing and monitoring; and
- Isolate all laboratory confirmed cases.
“The idea is to identify cases that might be at risk of getting the infection, and work to educate those people about the risks, and then work with them during what would be the incubation period for the infection.” , Weyer explained.
“So depending on when the person was infected, there is a three-week period during which they can be monitored to see if there are any signs or symptoms of monkeypox developing. Beyond this period, the risk [of contracting monkeypox] is then zero unless the person is again exposed.
The monkeypox case identified by the NICD on Wednesday was the first time the disease had been detected in South Africa, Weyer said. Prior to the 2022 outbreak, most cases of the disease were found in West and Central Africa, where the disease’s natural animal host resides.
Nature of monkeypox
Monkeypox is a very mild infection, Weyer said. It can be uncomfortable and disconcerting, but it is not fatal. Cases usually resolve on their own without any specific intervention and hospitalization is rarely required.
“Doctors can try to treat the symptoms — so fever or pain or any discomfort the patient might be feeling — and they do that on a case-by-case basis,” Weyer said.
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Monkeypox is less transmissible than smallpox and viruses like influenza or Covid-19. Prolonged close contact is usually required to transmit the disease from person to person, said Professor Adrian Puren, executive director of the NICD.
“It means, for example, face-to-face contact, where … droplets could be a form of transmission, as well as body contact. In other words, if there is contact during the sexual act, for example,” Puren said. It is also possible for the disease to be transmitted through laundry or clothing.
A person with monkeypox can become contagious within three days of showing symptoms of the disease, he continued. They remain contagious until the rash caused by the disease heals completely. The rash can last between two and four weeks.
Once a person contracts the disease, isolation is important.
Weyer pointed out that there is no evidence to suggest that physical or biological susceptibility to disease differs from person to person.
“Our biology works the same way, and for the virus, it is the same. So there is no selection in terms of which group is affected,” she said.
A fortuitous situation that developed early in this epidemic is that a large number of people who have contracted the disease are men who have sex with men, Weyer said.
“In the context of their social structure, the people they tend to mingle with, the people they have very close contact with, will also be men who have sex with men,” she said. declared.
“We communicate what is seen on the ground; we try to explain it by looking at the data and trying to make sense of it.
In the investigation of an outbreak, there are always characteristics specific to that outbreak, Puren said, adding that the NICD strongly condemns any form of discrimination against any group due to statements taken out of context regarding the disease.
Screening and vaccination
The best way to test for monkeypox is to test material from a rash or skin lesion, Weyer said. The NICD is working to increase the accessibility of testing.
“As with many outbreaks we have dealt with before, should the need arise there is excellent laboratory infrastructure in South Africa, and I think this has been demonstrated very well during Covid-19,” Weyer said. “It is possible to extend the tests if the need arises.”
There are vaccines against monkeypox. Some of them were not developed specifically for the disease, but rather for smallpox. The two diseases are closely related, although smallpox has been eradicated by mass vaccination around 1980.
“It is believed that people under 40 to 50 years of age are not immune to smallpox, and the effectiveness of [smallpox] the monkeypox vaccine is believed to be around 85%,” Puren said.
“So I guess the concern was that the fact that…we didn’t continue to vaccinate against smallpox, of course, [means] that there is now an immune deficiency.
At this point, however, no countries are implementing mass or population-wide vaccination programs against monkeypox, Weyer said. Cost-benefit analysis currently does not favor such an approach.
“[A mass vaccination programme] will require substantial investment to contain, in all likelihood, very few cases,” Weyer said.
“Of course, as with everything, we continue to look at the situation, and if the need arises to … resort to vaccination, then, of course, these decisions have to be made.” SM/MC