Divulgação, Notícias

Impact of Covid-19 on Reporting Neglected Tropical Diseases

A study that verifies the epidemiological profile of some NTDs in Brazil calls attention to the challenging scenario in the post-pandemic in relation to these diseases that already present brutal numbers in Brazil


Number of hospitalizations for visceral leishmaniasis, leptospirosis and malaria in 2020 showed a decrease of 32.87%, 43.59%, 29.31%, while dengue fever increased by 29.51% compared to averages from 2017 to 2019

In addition to all the impact caused by covid-19 itself, other harmful consequences to health, indirectly generated, are to be verified as a result of the pandemic in its different aspects. The consequences became evident as there was a delay in the diagnosis of pathologies in general, with the prevention and monitoring of endemic diseases being neglected by a significant proportion of the population. In addition, the public health emergency created by covid-19, impacted the notification of neglected tropical diseases (NTD), diseases that affect 1 billion people worldwide and mainly affect the poorest populations, which suffer from lack of basic sanitation, inadequate housing and living in precarious health conditions.

The abrupt drop in the notification of new cases of people affected by NTDs, which can lead to an explosion of cases in the post-pandemic, was identified in the study entitled Analysis of hospital admissions and mortality from febrile, infectious and parasitic diseases during the pandemic of COVID-19 in Brazil.

The study verified the evolution of cases of visceral leishmaniasis, leptospirosis, dengue and malaria in 2020, based on epidemiological information recorded in official databases, in the case of the Hospital Information System of the Unified Health System (SIH/SUS). According to the survey, between 2017 and 2019, the monthly average of admissions from January to August was 222.25 admissions for visceral leishmaniasis, 220.5 for leptospirosis and 160.67 for malaria. In 2020, between January and August, the monthly average was 125.38 hospitalizations for visceral leishmaniasis, 155.87 for leptospirosis and 113.25 for malaria, numbers that represent a drop in the average of hospitalizations in the order of 43.59%, 29.31% and 29.51%, respectively, compared to the averages for the three years before the pandemic.

To learn more about the subject, the Communication Department of the Brazilian Society of Tropical Medicine (SBMT) interviewed Dr. Stefan Vilges de Oliveira, epidemiologist and professor at the Department of Public Health at the Federal University of Uberlândia (UFU) Medical School and one of the authors of the study. Doctor of Tropical Medicine, Dr. Stefan Vilges de Oliveira also served as a technical consultant for the Pan American Health Organization (PAHO/WHO) and for the Health Surveillance Secretariat of the Ministry of Health (SVS/MS).

Check the interview in full:

SBMT: What was the main impact of Covid-19 on the notification of endemic diseases?

Dr. Stefan Vilges de Oliveira: Based on the analysis of epidemiological data on a set of endemic, infectious and parasitic diseases (Leptospirosis, Malaria, Leishmaniasis, Hantaviruses and Rickettsiosis) we observed a reduction in notifications of these diseases, which was accompanied by a reduction in the number of cases confirmed and the increase in the lethality rate. These results probably have as their cause the prioritization of the Covid-19 confrontation, where the entire health network was mobilized to meet the demands of the pandemic, and consequently, lower incidence diseases were left out. This impacted the detection of these diseases, generating underreporting and worsening clinical outcomes. The late detection of cases of low-incidence endemic diseases was responsible for the increase in the fatality rate.

SBMT: Could you talk a little bit about the control of endemic diseases in times of Covid?

Dr. Stefan Vilges de Oliveira: Epidemiological Surveillance, which has among its objectives to carry out prevention and control actions, is a strategy that has as one of its main premises the need to be carried out regularly and systematically. This means that health services need to be prepared to maintain surveillance, prevention and control actions on a continuous basis for all diseases and injuries within the scope of Health Surveillance.

In this sense, even understanding that public health resources are finite and that for some years the Unified Health System (SUS) has suffered from underfunding, it is necessary to seek to ensure comprehensive care and actions that are recommended by the Ministry of Health. Thus, the maintenance of routine actions for other surveillance programs should also be prioritized.

SBMT: What are the challenges if covid-19 becomes an endemic disease?

Dr. Stefan Vilges de Oliveira: The main challenge will be to include it in agreements with a large list of diseases and health problems that are already the object of action by the Health Surveillance and Assistance.

Ensuring resources (human and financial) for preventive actions that seek to reduce the transmission rate will be the object of intervention to be resolved in the short term.

In the long term, it is expected that with the expansion of vaccination coverage rates, we will have a reduction in the circulation of the infection. Covid-19 may be endemically maintained in small outbreaks in unvaccinated population niches. In this regard, the greatest efforts should be made to promote health education, which includes the understanding that the vaccine is necessary to control the disease. Parallel to these actions, a proactive surveillance of cases together with the strengthening of genomic surveillance should be able to monitor possible viral mutations that could threaten the protection that vaccines are providing.

SBMT: Do you believe that Brazil is experiencing an epidemic of endemic diseases?

Dr. Stefan Vilges de Oliveira: What is observed is a great epidemiological silence for the vast majority of endemic diseases that was caused by the pandemic. For infectious and parasitic febrile diseases, we observed that the pandemic significantly affected the records of these diseases and the statistics presented only reflect the “tip of the iceberg.” For chronic diseases, there is also a large demand repressed for health problems that only now with the gradual resumption of activities will begin to impact the SUS.

SBMT: In your opinion, has the pandemic increased or decreased surveillance of endemic diseases in urban and rural areas?

Dr. Stefan Vilges de Oliveira: For the vast majority of endemic diseases, surveillance was discontinued during the pandemic. Historically, Health Surveillance works with a reduced contingent of professionals and limited financial resources (when compared to SUS resources for assistance) which often makes health managers, who are responsible for carrying out the activities, have to prioritize one or another activity to be performed.

In this prioritization, endemic diseases of lower incidence are the most affected. The discontinuity of surveillance actions has great impacts on the proposition of public policies, as these are planned based on the epidemiological data collected and this is even more aggravated when we talk about endemic diseases that are considered neglected.

However, it is possible that for other diseases, such as respiratory (Influenza and its subtypes) with the pandemic, surveillance may have improved. Since, in the context of differential diagnosis, previously undetected Influenza cases, with the pandemic and a more active and sensitive surveillance system for detecting respiratory diseases, these may have benefited from better records.

SBMT: What to do to fight endemic diseases and eliminate the spread of viruses in Brazil?

Dr. Stefan Vilges de Oliveira: Strengthening the SUS! We need to have a resolute Primary Care that guarantees access and that, in an integrated manner, promotes the Surveillance of endemic diseases in its territory.

Strengthen Epidemiological Surveillance and understand that in the covid-19 pandemic context, Epidemiological Surveillance must precede assistance actions and save lives more resolutely.

Ensure regular and systematic notification, testing and epidemiological monitoring. Use the epidemiological data produced to act in a predictive way, anticipating disease cases.

SBMT: In your opinion, why did covid-19 impact immunization coverage? What to do to reverse this?

Dr. Stefan Vilges de Oliveira: At the beginning of the pandemic, the main message that was given was “Stay home.” The population partly complied with this request, and this was reflected in the low vaccine coverage subsequently observed. To improve these vaccination coverage indicators, we need to work on health education, seeking to promote an understanding of the need to keep the vaccination record up to date. People need to understand that they are subject to other diseases that are endemic and that can be as harmful to health as covid-19. Thus, proper communication with the population is essential.

SBMT: What advances are needed to overcome the global impact of neglected tropical diseases?

Dr. Stefan Vilges de Oliveira: We need to use the important experiences acquired in the pandemic to face Neglected Tropical Diseases (NTDs). We had vaccines developed and validated in record time and a volume of scientific information produced in a short space of time that saved many lives. I believe that we can take advantage of part of this acquired knowledge and replicate it to NTDs that historically suffer from little financial incentive and attention from the government.

SBMT: Could you talk about the spread of diseases linked to climate change and the displacement of endemic diseases?

Dr. Stefan Vilges de Oliveira: In Brazil, together with the health crisis promoted by covid-19, we have been watching with fear data that show an important environmental impact in our territory, especially in areas of the Amazon.

The numbers show that in recent years deforestation, burning and illegal mining areas have advanced to preserved natural areas.

It is known that approximately 75% of emerging diseases are of zoonotic origin and their main cause is climate change and changes in land use and occupation.

This movement of occupation of natural areas brings the imminent risk of new epidemics due to the contact of human populations with natural areas and pathogens. The observed environmental degradation may also modify the epidemiological-spatial-temporal patterns of already endemic diseases, expanding or modifying their areas of occurrence and thus affecting larger population groups and new susceptible populations.

SBMT: Can we say that the pandemic and climate and environmental changes created a scenario of uncertainty for Brazil with regard to endemic diseases? Why?

Dr. Stefan Vilges de Oliveira: Yes, the epidemiological data on endemic diseases recorded in Brazil during the pandemic do not reflect their real impact. As a result, it is likely that we are underestimating the risk of diseases that were “silent” during the pandemic and that may emerge with greater force, as they were without adequate monitoring.

SBMT: Brazil has a high rate of infectious and endemic diseases. Discreet and dangerous, do you believe that endemic diseases will continue to affect the country?

Dr. Stefan Vilges de Oliveira: Yes, absolutely! Many of the infectious and endemic diseases have a low incidence, affect vulnerable populations and for this reason are not prioritized within Brazilian public policies. There needs to be an understanding that NTDs are responsible for illness, disability and death and that it is the States duty to ensure comprehensiveness and equity of access to healthcare for the Brazilian population.

SBMT: Would you like to add something?

Dr. Stefan Vilges de Oliveira: I believe that knowledge of Epidemiological Surveillance was underutilized during the pandemic. Brazil has extensive experience in the control and eradication of various diseases and could have contributed in a more qualified way to prevention and control policies. The strategy of strengthening Hospital Care was prioritized over ensuring infection control.

If we observe, the vast majority of Brazilian municipalities used as an indicator of “pandemic control” the % (percentage) of occupied beds. There is a big mistake in this action, as recognizing this indicator as a way to relax restrictive measures is to assume that people will get sick and consequently will die given the natural history of a disease that does not yet have a specific treatment. For the next pandemics, we need to ensure that Epidemiological Surveillance actions are better implemented. That there is better testing and monitoring as a strategy to control the spread of the disease. Seek to strengthen and integrate Surveillance and Assistance actions. Improve risk communication, information quality and transparency. Foster the SUS, stimulate translational research and the development of evidence-based public policies.