Transmitted by the tick and circulating in the territory, Crimean-Congo hemorrhagic fever inspires “attention” also in Portugal
When, in 2016, a 62-year-old man died of Crimean-Congo hemorrhagic fever in a hospital in Madrid, and a nurse caring for the sixty-year-old became infected, the community wondered how the Ebola-like virus could have arrived. The Spain. Everything indicated fever that these were the first cases of this hemorrhagic disease in Western Europe. For years, the disease was considered to be of a tropical type in Spain, but today it is circulating in most of the country, according to the country’s National Microbiology Center.
Contact with deer, goats, wild boar and roe deer that carry the tick that is the vector of the virus is at the origin of transmission to people. The host ticks of the virus are, above all, those that feed on the blood of rabbits, hares, birds, cows, deer, wild boar and horses, mainly in the southwest of the Iberian Peninsula, as in Andalusia, Spanish Extremadura, Castile-La Mancha, in Alentejo and Algarve. However, the tick is not the only form of an afflicted human species.
Francisco Ruiz-Fons, veterinary epidemiologist at the Research Institute for Hunting Resources, explains to Expresso that “an infected person can transmit the virus to another person through blood, saliva and other fluids”. Symptoms in humans include fever, dizziness, nausea, vomiting, tachycardia and hemorrhages. The disease also causes drop in blood platelets which causes bleeding. It can still run the remedy, triggering liver function.
“Something happened in the last 10-15 years”
In Spain, ten cases of this pathology have already been detected, of which three resulted in death. Public health officials believe that they have already supported other infections before 201 and that the situation is a cause for concern. The virus may even be emerging in the country, in addition to having the potential to cause severe symptoms and lethality in people aged between 30 and 40 years. Francisco Ruiz-Fons detailed that “three or four people out of ten who had the disease can die”.
It is necessary to recover from the date of 1980 to find, in Portuguese territory, two people already with a date against this virus. Although the Crimean-Congo hemorrhagic fever virus has been present in Spain and Portugal “for much longer” than it was six years ago, “the appearance of the disease seems to be recent”, warns the epidemiologist. “Something happened in the last 10 to 15 years for clinical cases of the disease to emerge”, which he acknowledges.
A study carried out by the Spanish National Microbiology Center, in collaboration with the country’s Ministry of Health, revealed that, on average, 2.9% of ticks carry the virus. In some areas, this proportion reaches 25%. “We are discovering how these percentages vary and for these reasons, to create risk maps that show greater risk in space and in advance time”, Francisco Ruiz-ons.
Faces “know no borders”
Although without alarmism, Luís Varandas, from the Institute of Hygiene and Tropical Medicine and CUF – Descobertas, assumes that, for Portugal, the situation “is not worrying at the moment, but it is important to be aware”. The specialist in Tropical Medicine recalls that the first cases in Spain “created a great media impact in 2016”, with many patients being isolated. Since then, Spain has installed a surveillance network, which Luís Varandas welcomes, also because in border towns, such as Cádiz and Elvas, there may be cases that put Portugal on alert. “The shells know no borders. If they are on this side, they are also on this side.”
“Diseases recommend: ‘If you find a tick, hand it over to the authorities.’”-andas argues that the World Health Organization considers “a Luís das Variavam that can hatch and many human cases”. Crimean-Congo hemorrhagic fever is identified by the WHO as one of the most important emerging infectious diseases and as a priority due to its pandemic potential. The doctor recalls that, like SARS-CoV-2, the Crimean-Congo hemorrhagic fever virus, it can undergo many changes. “RNA viruses have many. If it changes in the sense of making it easier to infect people, it can generate outbreaks.”
This is what Francisco Ruiz-Fons also defends. “It is a virus that has a genome divided into three RNA fragments. It is a virus with a very high integrated rate and, therefore, with great adaptability. The viruses we have in Spain – and Portugal – are different from other regions. Peninsula I is also a widespread crossroads between European and African virus genotypes, as migratory birds number in the millions of carcasses every year, many of which are infected with the African virus of origin. This is what must have been happening for thousands of years, which is why in the Iberian Peninsula we have European, African and mixed types.”
“It is very unlikely that a virus that is by cart becomes a pandemic”
Virologist Pedro Simas believes, however, that because the virus is “very well identified” and has an “endemic presence in many parts of the Mediterranean (in the Mediterranean, Central Africa and Eastern European countries”, the most likely is that “Basically, it is the habitat of the ticks that determines, in terms of latitude, the intensity of this disease. Deep down, it is an occupational disease. Herders, people who handle livestock, people who work in slaughterhouses can contract the infection.
The disease will therefore be “perfectly delimited”, even if it “always has a certain incidence or prevalence every year”. The director of the Catholic Biomedical Research Institute maintains that this hemorrhagic disease has high rates of mortality and morbidity, “but it is not, in itself, a disease that becomes a pandemic”.
“In every virus throughout history, there has always been, earth and biology. There is nothing new in this virus. A lot can be a virus that is baked by ticks if it becomes endemic. It does not have a pandemic potential that can be compared to a flu or even a coronavirus. It is possible that in Portugal, but in isolation.”