Israel has a large stock of vaccines against monkeypox, though the Health Ministry does not plan to launch a vaccination campaign or to try to halt the spread of the disease through contact tracing and isolation.
To date, only one Israeli has been diagnosed with the disease; two other possible cases were ruled out on Sunday.
Health officials both in the ministry and outside it said Israel should purchase more vaccines as a precautionary measure. The existing vaccines were stockpiled against smallpox.
Until the early 1980s, Israelis were routinely vaccinated with the smallpox vaccine, which was made by the Institute for Biological Research in Nes Tziona and is similar to other smallpox vaccines made overseas. The Health Ministry still does not know the level of protection against monkeypox provided to those who received the smallpox vaccine before routine vaccination ended.
Since routine inoculations ended, the ministry has kept a stockpile of the vaccines out of fear smallpox could be used as a biological weapon.
Ministry officials said a vaccination campaign against monkeypox isn’t necessary as the disease is less infectious and dangerous than the coronavirus. Morover, since the vaccine contains a live-virus, vaccination often produces side effects that resemble symptoms of the actual deases. This means that some individuals, such as those with certain skin diseases or weakened immune systems, cannot receive the vaccine.
“We’re leaning toward not using these vaccines for all kinds of reasons, including the fact that using them involves some risk for part of the population and the fact that during the long period when they weren’t used, biological and immunotherapy drugs that affect the immune system have entered into use for treating various diseases, and we don’t know how the vaccine would affect them,” said Dr. Oren Tsimhoni, head of the infectious disease unit at Kaplan Medical Center in Rehovot and a member of the government’s advisory panel on epidemics.
Because of the existing vaccine’s side effects, the Health Ministry also plans to buy a more advanced vaccine against the virus called Imvamune. Imvamune also contains a live-virus, but unlike Israel's current stockpile, it can't reproduce within the body and therefore produces fewer side effects. As a result, those who can't recieve the older vaccine will be able to recieve imvamune.
Prof. Dana Wolf, head of the clinical virology unit at Hadassah Hospital, Ein Karem, said that because it is both effective and safer, Imvamune is currently being given to laboratory workers and others at high risk of exposure to the virus.
The ministry also has stocks of medicines used to treat monkeypox. Cidofovir, for example, is effective at treating the virus but can damage the kidneys. The ministry also plans to purchase two other drugs that can be used to treat the virus, including Brincidofovir, a safer and more advanced version of Cidofovir, and Tecovirimat, which is used to treat particularly serious cases of monkeypox.
“We aren’t in a situation where we need to panic over the cases of monkeypox that have been discovered,” Wolf said. “From what we’ve seen so far, the disease is relatively mild, it isn’t transmitted through the air and, based on initial evidence from gene sequencing in Europe, the virus doesn’t seem to have mutated.”
“Nevertheless, as we know, viruses can surprise us,” she added. “So we need to deal with it and prepare.”