Скачать с ютуб New mpox strain is changing fast and African scientists 'working blindly' в хорошем качестве

New mpox strain is changing fast and African scientists 'working blindly'

Scientists studying the new mpox strain that has spread out of Democratic Republic of Congo say the virus is changing faster than expected and often in areas where experts lack the funding and equipment to properly track it. That means that there are multiple unknowns about the virus itself, its severity and how it is transmitting, complicating the response, half a dozen scientists in Africa, Europe and the United States told Reuters. Mpox, formerly known as monkeypox, has been a public health problem in parts of Africa since 1970, but received little global attention until it surged internationally in 2022, prompting the World Health Organization to declare a global health emergency. That declaration ended 10 months later, but cases continued to increase in Africa. Now, a new strain of the virus, known as clade Ib, has the world's attention again after the WHO said earlier this month that its fast spread in DR Congo and to neighboring countries was a new health emergency. The strain is a mutated version of clade I, a form of mpox spread by contact with infected animals that has been endemic in Congo for decades. Mpox typically causes flu-like symptoms and pus-filled lesions and can kill. Congo is facing both clade I and clade Ib outbreaks, and has had more than 18,000 suspected cases and 615 deaths this year, the World Health Organization says. There have also been 222 confirmed clade Ib cases in four African countries in the last month, plus a case each in Sweden and Thailand, both people with a travel history in Africa. "We are still working blindly in Africa. We don't have the required knowledge about mpox's natural history, transmission dynamics, risk factors of mpox," Ogoina said. Ogoina, who first raised the alarm about potential sexual transmission of mpox in 2017, now an accepted route of spread for the virus, also expressed concern about the virus's rapid evolution. He said it took clade IIb in Nigeria five years or more to evolve enough to spread in a sustained way among humans, sparking the 2022 global outbreak. Clade Ib has done the same thing in less than a year. Mpox is an orthopoxvirus, the same family that causes smallpox. Population-wide protection from a global vaccine campaign against the disease 50 years ago has waned, as the campaigns stopped when the disease was eradicated. Genetic sequencing of clade Ib infections, which the WHO estimates emerged mid-September 2023, show they carry a mutation known as APOBEC3, a signature of adaptation in humans. The virus that causes mpox has traditionally been fairly stable and slow to mutate, but APOBEC-driven mutations can accelerate viral evolution, and the response has been complicated by several mpox outbreaks happening at once. In the past, mpox was predominantly acquired through human contact with infected animals. That is still driving a rise in Congo in cases of clade I – also known as clade Ia - likely due in part to deforestation, increased consumption of bushmeat and other factors, scientists said. The mutated versions, clade Ib and IIb, are spreading so often through sexual transmission that it is now essentially a sexually transmitted disease, said Salim Abdool Karim, a South African epidemiologist and chair of the Africa CDC’s mpox advisory committee. Most of the mutated clade Ib cases are among adults, driven at first by an epidemic among female sex workers in South Kivu, Congo. The virus can also spread through close contact with an infected person, which is probably how clusters of children are getting clade Ib, particularly in Burundi, and in eastern Congo’s displacement camps, where crowded living conditions may be contributing. Children, pregnant women and people with weakened immune systems may be at greater risk of serious mpox disease and death, according to the WHO. Clade I has typically caused more severe disease, with fatality rates of 4%-11% compared to around 1% for clade II, but Ogoina said data from Congo suggests few have died of the new Ib version, and he feared some data is being mixed up. More research is urgently needed, but three teams tracking the multiple mpox outbreaks in Africa say they cannot even access chemicals needed for diagnostic tests. Planning a response, including vaccination strategies, without this is difficult, the scientists said. Karim said around half of cases in eastern Congo, where Ib is particularly prevalent, are only being diagnosed by doctors, with no lab confirmation. Getting samples to labs is difficult because the healthcare system is already under pressure, he said. Around 750,000 people have fled to the area amid fighting between the M23 rebel group and the government. Despite these challenges, Karim remains optimistic about controlling the outbreak using established public health measures. "This is not rocket science," he said. "We do this for other infections and so we can do it for mpox." (Production: Catherine Schenck, Tife Owolabi, Angela Ukomadu, Cooper Inveen)