Cross-epidemic: amid apprehension with the coronavirus, authorities warn of the increase in dengue cases

Publicação: 11 de March de 2020

The numbers of dengue cases in the country are expected to grow as the peak of the epidemic occurs between the months of March and May

Despite affecting the population in the same period, dengue and coronavirus have completely different mechanisms of contagion

While Brazil is making efforts to prevent a possible epidemic of the coronavirus, the country is in state of alert due to the outbreak of an old-known tropical disease: dengue. Data from the latest epidemiological bulletin from the Ministry of Health show that the number of probable cases of the disease, those that are reported by states, grew by 19% in the first five weeks of 2020 compared to the same period in 2019. Between December 29 and February 01, 94.149 probable cases were reported, while in the same period last year, 79.131 were recorded. In 2019 about 2.242 million cases of the disease were registered. Acre, Mato Grosso do Sul and Paraná are the states with the most worrying situation so far. The advance of cases is common at the beginning of the year due to the rains, which have increased in recent weeks. The difference of this moment is that we live a new outbreak of the disease, something that historically happens between two and three years due to the recirculation of new types of virus.

While people drive their own car, alone, with a mask, closed windows, air conditioning on, protecting themselves, the cruel Aedes aegypti continues to fly free, light and loose, spreading the disease. And cases are expected to continue to grow, as the peak of the epidemic occurs between the months of March and May. In this early 2020 alone, at least 14 people died. Brazil currently has an average of 44 dengue cases for every 100 thousand inhabitants, an increase of 70% over last year. What worries health authorities is the existence of a new subtype of the virus – type 2, which causes hemorrhagic dengue, which is lethal. Brazil ranks first in cases of dengue in the Americas. When the agenda is environmental health, Brazil seems to be following a fine and dangerous line, in terms of precaution, prevention and effectiveness.

In the opinion of the professor at the Federal University of Bahia (Ufba), virologist Gúbio Soares, an exaggerated and unnecessary panic was created over the coronavirus. The researcher’s main concern now is that the attention given to the coronavirus causes an outbreak of dengue. “A big mistake is being made. We are in full growth of the dengue outbreak in Salvador. Chikungunya is growing in Bahia and Zika is too, we even have an outbreak in Periperi, located in the Salvador suburbs, of a mysterious disease. The dengue campaign is forgotten, in plain summer. And we don’t find an effective campaign. This is dangerous, as we may have many deaths in Brazil”, he warns. Still according to him, the fight against coronavirus, together with dengue, will demand a lot from the Unified Health System (SUS). “There will be a high cost for control and prevention and for that, the government should invest more resources to control and prevent these diseases”, he emphasizes.

Professor of infectiology at the Federal University of Minas Gerais (UFMG) Dr. Unaí Tupinambás warns of the real risk of the two epidemics occurring in Brazil, remembering that the beginning of autumn reduces the cases of arboviruses and increases the risk of respiratory diseases. According to him, if we have a coronavirus epidemic, its control will necessarily pass through Primary Care, since more than 80% of cases are mild. The Ministry of Health’s Family Health Strategy (ESF) professionals will be the first to ‘enter the field and the last to leave’. “During these times of dismantle of these teams, as well as with a reduction in health financing – to give you a picture, Health investments were cut in R$ 9 billion in 2019 – the fight against coronavirus, together with dengue, will demand a strong SUS. The confrontation necessarily passes through it, even though it is threatened by the reduction of investments and the family health program. These issues all add up to Constitutional Amendment 95, which established the public spending limits”, he points out. According to the professor, in order to face this emerging virus, we will have to rethink the financing of SUS, otherwise our confrontation is at risk of falling far short of what is necessary for the containment and care of those affected.

Public health cross-epidemic risks

PhD in Statistics and Researcher at the Scientific Computing Program (PROCC) of the Oswaldo Cruz Foundation (Fiocruz), in Rio de Janeiro, Leonardo Bastos explains that the cross epidemic would be a major problem for the health service, mainly with an increase in serious cases the two diseases. “In terms of comparison, we can observe the record of hospitalizations for Influenza and dengue from SIH/SUS in the graph below where we note that the volume of cases of Influenza is less than that of dengue, and at the national level we did not have a cross epidemic scenario. In 2009 alone, with the arrival of H1N, we had a large number of cases of Influenza, possibly related to the arrival of H1N1, but the epidemic did not coincide with the dengue epidemic of that period”, he weighs.

Number of intentions for dengue (severe dengue + hemorrhagic dengue) and hospitalizations by Influenza, per month: January 2008 until December 2019. Graphic elaborated by Dr. Leonardo Bastos from Datasus data (http://datasus.saude.gov.br/acesso-a-informacao/morbidade-hospitalar-do-sus-sih-sus/)

Still according to Dr. Leonardo, the flu epidemic usually occurs in winter while the peak of the dengue epidemic and other diseases transmitted by Aedes occur in late summer/early spring. Therefore, if the new coronavirus behaves like seasonal influenza, then this year’s epidemic should not coincide with that of dengue. Another problem, according to him, to be considered in case the two epidemics happening at the same time would be the lack of knowledge about the effects of the co-infection between arboviruses and the coronavirus.

The tendency for dengue is to increase in the number of cases, arboviruses have a strong dependence on the climate, since the transmission cycle depends on a certain combination of temperature, humidity and precipitation. So, we can expect in the coming weeks a significant increase in cases of arboviruses. “As for the coronavirus, we can see an increase in imported cases and, possibly, some autochthonous cases, but if it behaves like other flu viruses, I would say that we will not see high numbers, especially in relative terms when compared to the numbers of dengue”. On the other hand, if a possible coronavirus epidemic behaves like the H1N1, epidemic, then there will be an explosion of cases in late spring/early winter, which may coincide with the end of the flu epidemic”, says the Fiocruz researcher.

Member of the Brazilian Society of Tropical Medicine (SBMT), Director of the Minas Gerais Society of Infectology (SMI) and International Relations of the Brazilian Society of Infectology (SBI), Dr. Carlos Starling is categorical in stating that there is a risk of the accumulation of cases of dengue, coronavirus and influenza in the coming months. He describes that the peak of dengue actually occurs between April and May, a time when we should have more cases of coronavirus, which is arriving now and each person can transmit it to two or three others, and this will occur in the period of greatest incidence of dengue, between March and May, when there is more infestation of Aedes aegypti. “During this period, Influenza cases also begin. What encourages us is that the government is advancing vaccination correctly to the end of March”, he points out. It is worth remembering that for dengue there is also a specific vaccine for people who have already had the disease, in addition to the Aedes containment measures. Regarding the coronavirus, we only have the prevention, containment and personal and collective hygiene measures. “But the risk of a coincidence does exist, which can lead to an overload on the health system. We can have one problem aggravating the other, congesting the health system”, he says.

The risk, perhaps more than the epidemic itself, is that the population’s panic could lead to an unnecessary rush and system overload. According to Dr. Starling, the most powerful weapon to avoid the panic and stress of the population in relation to these problems that we can face is information. He stresses the need to maintain information disclosure, transparent communication, in addition to the adoption of guidance measures for home treatment of cases, especially of coronavirus, which does not require hospitalizations. “The less people stay in the emergency rooms in hospitals, the lower the risk of transmission and causing a problem that worries us a lot, which are infections in health professionals, that leads to a lot of absenteeism, and ends up overloading the system even more”, he says. Another suggested measure is to monitor patients more and more at home, with guidance and fluid contact from the health system, making use of technology, such as WhatsApp, which can give people more peace of mind. “Despite being a new situation, it is something that we will have to learn how to do”, he acknowledges. Another concern mentioned by Dr. Starling refers to people with less purchasing power, who should make more use of the free services provided by SUS. “Will he have the structure to assist all those people who need it and, mainly, to monitor them at home, considering that the number will be quite expressive”, he wonders.

Past epidemics show that the coronavirus should be controlled. Panic does not help to solve a collective health problem. But if we don’t have a very strong health system, we are going to have a huge difficulty to contain this new epidemic and the old ones already known.

Brazil increases diagnosis for coronavirus

The Ministry of Health will expand the laboratory capacity for diagnosis of coronavirus throughout the national territory with the distribution of 30 thousand diagnostic testing kits (Berlin protocol), specific to COVID-19. Then, gradually, they will be expanded to all 27 Central Public Health Laboratories (LACENs) in the country. The announcement was made on March 02 by the Minister of Health, Luiz Henrique Mandetta. Initially, 10 thousand diagnostic kits will be distributed to LACENs in the states of Amazonas, Pará, Roraima, Bahia, Ceará, Pernambuco, Sergipe, Rio de Janeiro, Espírito Santo, Minas Gerais, Federal District, Mato Grosso do Sul, Rio Grande do Sul, Paraná and Santa Catarina, covering all regions of the country. The Oswaldo Cruz Foundation (Fiocruz), in Rio de Janeiro, through the Biomanguinhos laboratory, started the production and distribution of the testing kits on March 04th.

The Secretary of Health Surveillance of the Ministry of Health, Wanderson de Oliveira, pointed out that the Ministry will train all central laboratories in the country to increase surveillance for the disease. “These states will be the first to start carrying out the tests and, within 20 days, we will have all the central laboratories in Brazil carrying out the specific test. We have to expand surveillance. We are training the states and, thus, we will have more capacity to carry out the tests. We are expanding mainly because we are entering the season of respiratory diseases”, concluded the secretary.

Currently, four laboratories carry out the coronavirus diagnostic test: national reference laboratories, Fiocruz, in Rio de Janeiro, Instituto Evandro Chagas (IEC), in Pará, and Instituto Adolfo Lutz, in São Paulo, in addition to the Central Laboratory of Goiás, which was trained to perform the specific exam for coronavirus of Brazilians repatriated from China who were quarantined at the Anápolis air base (GO). The expectation is that the laboratories that receive the kits are already prepared to start the diagnostic process for the coronavirus within 20 days. In addition to the diagnostic test of the Berlin protocol, the Biomaguinhos laboratory will also start the production of 3 thousand test kits according to the CDC protocol, which will be used only as a control. In addition, the professionals of these laboratories will also be trained by teams from Fiocruz and IEC, to carry out the procedure in a qualified manner. The trainings will be in loco starting from the arrival of the kits in the states.

To keep the population informed about the new coronavirus, the Ministry of Health daily updates the data on the IVIS Platform, with numbers of discarded and suspected cases, in addition to the definitions of these cases and any changes that may occur in relation to the epidemiological situation.