The current outbreak of monkeypox that has led the World Health Organization (WHO) to declare the confinement a "public health emergency of international importance" presents symptoms, manifestations and complications different from those previously described in other outbreaks of this pathology.
This concludes the most exhaustive study on monkeypox carried out to date in Spain, carried out in the two most affected areas of the country, Madrid and Barcelona, and published in the journal "The Lancet".
The research, the result of collaboration between the 12 de Octubre University Hospital, the Germans Trias University Hospital and the Fight Against Infections Foundation and the Vall d'Hebron University Hospital, with the collaboration of the London School for Hygiene and Tropical Medicine (LSHTM ), indicates that skin-to-skin contact during sexual intercourse is evidenced as the dominant factor in the transmission of monkeypox, above airborne transmission.
Our study, Cristina Galván, a dermatologist at the Hospital Universitario de Móstoles in Madrid, tells ABC, has found that skin samples are more frequently positive and reflect a greater abundance of viral genome than samples from other areas such as the throat. In the context of a sexual relationship, she adds, “this intimate contact with the skin or external mucous membranes of an affected person undoubtedly occurs. Positive PCR for monkeypox virus has been found in vaginal secretions and semen, but its infectivity and, therefore, whether it can be transmitted through these fluids remains to be determined.
At this time, he warns, with the data we have, rather than stating that it is a sexually transmitted infection, "we must say that it is an infection that is transmitted during sexual intercourse."
This, the researchers write, entails a series of significant implications regarding the approach to the disease.
First of all, the authors confirm, the change in the transmission route from respiratory contact to direct contact compared to previous outbreaks may promote the spread of the disease through sexual networks.
The current outbreak presents symptoms, manifestations and complications different from those previously described in other outbreaks of this pathology
Until now, points out Dr. Galván, the aerated path has been considered a mode of transmission in the classic way of being confined. In the current outbreak, "the point of entry of the germs is different and can generate an immune reaction of the affected person, which is also different, which leads to an atypical clinical picture."
Taking into account the epidemiological data of the cases of the current outbreak, the expert indicates, “because the respiratory route does not have a significant participation in the transmission. The number of affected is already abundant and cases of transmission in circumstances other than sexual contact are almost non-existent.
But he prefers to be cautious. “In cases of classic monkeypox -which has affected endemic countries or in outbreaks limited to non-endemic countries after a trip or other sporadic contagion episode- the presence of the virus in the respiratory mucous membranes can be demonstrated. Just as its detection is achieved in genital fluids and saliva, research is very important, work is being done to determine its ability to transmit the infection.”
In our opinion, the implication that its analysis is crucial is “crucial to the determination of relevant public health measures. And the consequences for those affected are also, since the restrictions and isolation to which they must submit after contagion can be significantly modified.
In short, “since the monkey virus can present itself with atypical manifestations, health professionals should have a high index of suspicion of the disease, especially in those people who live in areas with high transmission, or with potential exposure.
In this case, this researcher from the Lluita Foundation, STI Skin NTD Unit points out that, although it is true that the clinical presentation of the cases of the current outbreak is completely atypical, "however, except for doctors who treat patients in endemic areas and we needed to have this diagnosis among the possible ones, this disease was very unknown” and believes that the medical community is learning about classical monkeypox thanks to this outbreak.
At the moment, says Galván, “we cannot know the percentage of patients who have remained undetected, either because this possibility has not been taken into account or because they have had few symptoms. But we do have ongoing studies aimed at answering this question, which is so important for controlling the spread of the disease."
In addition, he points out, the clinic is atypical compared to the classic one, but it follows patterns that facilitate diagnostic suspicion.
We cannot know the percentage of patients that have been detected without detecting
Also, the article explained, that because of the short incubation period, "pre-exposure vaccination of risk groups is likely to be more effective than post-exposure vaccination for infection control."
However, as this researcher acknowledges, “the availability of vaccines is, at the moment, insufficient. As long as this is the case, we must give priority to people with the highest risk of contagion or of developing a serious illness.”
In this case, if we had all the necessary doses, he adds, “all people with a high risk of sexually transmitted disease would be vaccinated. That is, a population similar to its HIV pre-exposure prophylaxis indication. It would also vaccinate intimate contacts, such as sexual ones, of an affected person and people who are especially vulnerable due to poor immunity, either close to people at risk or who have had close contact, although not intimate, with someone affected.”
In May 2022, the first autochthonous cases of monkey virus were reported in Europe, giving rise to an outbreak that is still active in 27 countries and has caused more than 11.000 confirmed cases. Spain is the most affected country on the continent with more than 5.000 diagnosed cases.
The scientific community continues to have little information on the epidemiological, clinical and virological characteristics of the current outbreak of monkeypox.
Health professionals must have a high index of suspicion of the disease
The now public study includes an exhaustive evaluation of these same aspects (epidemiology, clinical and virological characteristics) of 181 participants diagnosed with hospitalization in very large hospitals in Spain.
The work confirmed the clinical features observed in other retrospective analyses, but the larger sample size and systemic clinical examination revealed some previously unreported complications, including proctitis, tonsillar ulceration, and penile edema.
The article also establishes the relationship between types of sexual practices and clinical manifestations. One of the most important findings is the high viral load found in genital and oral lesions, with a difference in value of very low in the respiratory tract.
The results show that of the 181 confirmed cases, 175 (98%) are men, 166 of whom identify as men who have sex with men. The median length of the confinement incubation period is stable at 7 days.
