Still a long way to go to eradicate monkeypox
SINCE the start of the monkeypox outbreak in January, cases have climbed to more than 73,000 globally in 109 locations. Extraordinarily, 99 of these have never reported monkeypox cases before. Twenty-eight people are known to have died. This rapidly spreading outbreak has led the World Health Organisation to declare a global health emergency, its highest level of alert.
In Australia, about 140 cases of MPX have been reported, mainly in Victoria and NSW and the vast majority of these cases are in men who have sex with men, and, generally, in the age group 21-40 years. Fortunately, there have been no deaths reported in Australia due to MPX.
This is the first time that we have seen a global surge of cases of MPX due to human-to-human spread. In the past the virus was generally acquired from contact with animals in tropical rainforest areas of central and west Africa.
Rodents and non-human primates are considered to be the natural animal reservoir of MPX and it is transmitted to humans through close contact with an animal, or an infected person, or with material contaminated with the virus like bed linen and bath towels.
To transmit the virus actually requires close and prolonged contact with body fluids, such as respiratory secretions and skin lesions of an infected person, or close contact with recently contaminated objects.
This puts health care workers, household members and other close contacts of active cases at greater risk. The disease is usually mild, however, and lasts from 2-4 weeks. Fever, rash, swollen lymph glands and vesicles (sores) on the skin are common symptoms, however, it may lead to complications involving pneumonia, blood poisoning, encephalitis or infection of the eye with possible loss of vision. In children, and all those with immunocompromised disorders, the risk of disease severity and death is increased.
There are also increased risks during pregnancy as the virus can be transmitted to the foetus or to the newborn child; spontaneous abortion and stillbirth have occurred in cases of MPX infection during pregnancy.
To date, outside of Africa, almost all cases have been in the male-tomale group, especially in men with multiple partners and those attending group events. It is important that the message is spread that people should stay at home and isolate until the sores have healed to help limit spread.
Monkeypox has not been previously described as a sexually transmitted disease, however, given the current transmission pattern, it clearly shows it now is.
Also, there may be an unusually short 24-hour incubation period following sexual contact. As it is also a respiratory virus, aerosol transmission is possible.
Although monkeypox has a distinctive rash that appears on the palms of the hands and soles of the feet, it is sometimes confused with chickenpox (which is a herpes virus) and lesions on genitalia can be mistaken for sexually transmitted infections such as syphilis, gonorrhoea and chlamydia.
This is a highly contagious virus and as a global community we must be on high alert. Fortunately, we are well armed with vaccines to combat both the illness and disease spread.
Universal vaccination against smallpox in the past was not only effective in eradicating the disease but it also gave 85 per cent protection against MPX. However, a more updated MPX vaccine is being developed that does not carry the risk of causing a serious infection in immunosuppressed persons as seen with smallpox vaccine. These vaccines should help reduce spread considerably.
But vaccination and antiviral drugs alone are unlikely to halt the march of MPX around the world.
We also know that the current MPX virus causing the global surge is more infectious than the previous MPX viruses circulating in Africa in past decades.
Vaccine should be offered to persons at risk such as front-line health care workers including laboratory personnel. International travellers also need to be made aware of the risks.
MPX can also be transmitted back to animals though close contact, including pets, domestic animals and wildlife, and contact with animals should be avoided by persons infected with MPX.