Alex Almuedo is a senior specialist physician at the International Health Service of the Hospital Clínic in Barcelona, a center that has one of the few isolation units in Spain and from where the evolution of the new outbreak of monkeypox, known as mpox, is being closely monitored. His research, through the ISGlobal Institute, focuses on infectious diseases. In addition, he has worked in countries such as Bolivia, Mozambique, Sierra Leone and Nigeria, and knows the health system of the Democratic Republic of Congo (DRC), the epicentre of the new spread of the virus.
Almuedo shares the caution of the European and Spanish health authorities, who for the moment rule out any mass vaccination and border controls. Beyond the African continent, the only country to have detected a case of the new variant is Sweden. However, the greater spread and severity of the current epidemics, caused by clade Ib of the virus, have put the WHO on global alert.
What surveillance activity does a hospital like the Clinic have today regarding the new subvariant of monkeypox, taking into account that the risk of transmission in Europe is low and in Spain no cases have been detected?
At the Clinic, we created a mpox surveillance group that has remained active since the wave of epidemics was detected at the end of 2022 outside the area where it is considered endemic, that is, in Central and West Africa. Since then, this unit has been dedicated to supervising these cases or when there are suspicions. Since the beginning of the year, I would say that about twenty cases have been detected. But it must be remembered that this is the clade II variant, while the most recent [el que ha provocado la declaración de emergencia de la OMS] is clade I b.
Until now, we knew that clade I was more severe, with more mortality, that it affected more pregnant children and that it was more reported in remote rural and jungle areas, mainly in the DR Congo. However, since the end of 2023, we have observed this new clade, called Ib, in certain areas of the African country, such as South Kivu. What we know about clade I is that it has the particularity of presenting more viremia – more circulation of the virus in the blood and affecting more organs – and that it affects children more. Ib seems to affect the young adult population more. It is difficult to discern because the foci of the different variants are mixed in the country.
What do we know today about its impact on the child population?
If we look at the clade that spread in 2022, clade II, these were more localized lesions: cutaneous, localized on the skin, and which caused more generalized symptoms – a more flourishing infection – in people with immune problems. On the other hand, clade I generally presents a more flourishing infection, with more fever and a generalized rash. In groups such as those under one year of age, mortality has increased. It is almost four times higher than in those over 15 years of age. These are population groups at greater risk of systemic diseases, which escape the control of the defenses, as is the case with pregnant women or people with immunosuppression.
What is this due to?
This is an epidemiological observation. In general, clade I is more related to transmission within family units, which affects children more. But be careful, it is also true that this may be due to the fact that the population over 40 or 50 years old may be partially protected by the old smallpox vaccine. Many factors may be involved. From clade I, we also know that it can be transmitted through certain surfaces, such as hygiene utensils or hospital beds, but we know this based on epidemiological observations.
To avoid alarmism, some fundamental differences regarding covid have been highlighted, such as the fact that transmission is not airborne or that it only spreads when one has symptoms.
The transmission of Clade I through respiratory secretions has been described, but it must be face to face. That is, the drop leaves the mouth of your interlocutor and reaches you. Nothing to do with the type of transmission of covid and aerosols. In addition, the longest period of infection occurs when there are lesions, by contact with them. Once these are resolved, it is considered that it is practically impossible to be infected.
There are also doubts about the effects of current monkeypox vaccines or available treatments.
We still don’t have solid data on this. Research suggests that the vaccine against clade II should also be effective against clade I, but the percentage of reduction cannot be known. As for antiviral treatment, Tecovirimac worked particularly for severe and serious cases in the 2022 outbreak, but it seems that its effectiveness is not as effective with clade Ib. This is also why WHO has made this call to intensify research to address this.
The WHO’s declaration of an international emergency has been much talked about. Does that seem right to you?
This is a call for an international response. To arouse political attention, donations and in general a global mobilization of resources to improve the health infrastructure of the most affected areas of Africa. We are talking about jungles or rural areas where patients have delayed access to care.
This call should also serve to improve training, epidemiological surveillance and to stimulate research during the epidemic, to analyze the measures that are adopted along the way. The previous epidemic, that of 2022, received a fairly good response, and now the emergency declaration should serve to apply all these countermeasures in a country like the RCD, where it is much more complicated to deliver medicines and aid.
On the other hand, it must be taken into account that some studies have pointed to a mortality of this subvariant of 10%, although others have specified that with correct measurements it is reduced to 2%. And these are data strongly conditioned by the remote access of the population to health resources.
On the other hand, the EU and the Spanish government have so far ruled out widespread vaccination or border controls. Do you share this position?
It is prudent and at the same time appropriate. The outbreaks are very limited to the DR Congo, in addition to its border countries. In the other countries that are on the list of those affected, this is not so much the case. Kenya, for example, is on the list, but it is because of a truck driver who went to work on the other side of the border and came back infected. Something similar happened in Uganda. It is a mining area with a high mobility of workers.
But from the Spanish point of view, few travelers go to the DR Congo. Add to that the fact that they have to go to jungle areas and come into contact with a disease that is easier to detect than others. It does not seem that travelers in general are at risk. But be careful: epidemiologically, everything can change. So we are talking about in a week.
Would you like to add any measurements?
I believe that those adopted are appropriate, beyond not creating excessive concern and providing everyone with correct and adequate information. What we must focus on is epidemiological surveillance: detecting all suspected cases, with compatible symptoms, so as not to fall behind.
What would be a suspected case today?
We are waiting for the final protocols that the health authorities are developing. In our opinion, this is any clinic compatible with the disease, with the addition of having been in contact with a person who has suffered from the epidemic or who has traveled in the last 21 days, which is the incubation period, to the RC Congo or other countries with confirmed cases. This, with the exception of some workers in the affected areas, such as humanitarian workers, is unlikely.
