Fiocruz expands monitoring of Delta hepatitis in riverside communities

Silent, Delta hepatitis (HDV) has been worrying Fiocruz researchers and health authorities in riverside communities located in the southern region of Amazonas, where a team of researchers from Fiocruz Rondônia's Molecular Virology Laboratory and health professionals from Lábrea-AM traveled last June. On the banks of the Purus River, the city of 45,000 inhabitants – 407 km from Porto Velho and 850 km from Manaus – has approximately 1,400 reported cases of the disease and only 140 patients being monitored, according to the Rapid Testing and Counseling Center (CTA) of the Municipal Health Department (SEMSA-Lábrea).

Between 2000 and 2022, 4,393 cases of Delta hepatitis were diagnosed in Brazil. The highest incidence occurred in the North Region, with 73.1% of cases, followed by the Southeast (11.1%), South (6.6%), Northeast (5.9%) and Central-West (3.3%). In 2022, there were 108 new diagnoses, with 56 (51.9%) confirmed cases in the North Region and 23 (21.3%) in the Southeast. The data is available in the latest Epidemiological Bulletin on Viral Hepatitis (2023) published by the Ministry of Health's Health and Environmental Surveillance Department and reveals the seriousness of the public health problem, which is added to the numerous health demands that these hard-to-reach locations in the Amazon face on a daily basis.

In Lábrea, the team of researchers and health professionals visited the riverside communities of Várzea Grande and Acimã, on the Purus River. Over two days, rapid tests and laboratory exams were carried out, but the team's main focus was on diagnosing and screening for viral hepatitis, especially Delta hepatitis, which is the most aggressive type. Clinical care for 40 patients who had already been diagnosed with the disease in previous actions was provided by gastroenterologist and hepatologist Eugênia de Castro e Silva, from Porto Velho's Viral Hepatitis Outpatient Clinic.

In June, 113 residents were seen in the two communities, 16 of whom were diagnosed with hepatitis D. The samples are taken to Fiocruz Rondônia where they are processed and evaluated and the individuals with a positive diagnosis are assisted by the Lábrea health team and the Viral Hepatitis Outpatient Clinic, which helps with the clinical management of the patients.

Expanded patient monitoring

The team's coordinator, Deusilene Vieira, head of the Molecular Virology Laboratory, explains that the screening and monitoring of viral hepatitis had been carried out in Rondônia, but expanded to the riverside communities of southern Amazonas in December 2023, following the arrival at Cemetron Hospital, in Porto Velho, of two brothers from Lábrea, aged 19 and 23, with suspected superinfection with the Delta hepatitis virus. On that occasion, Fiocruz Rondônia was invited to carry out viral load tests on the patients, using the molecular method for quantifying the HDV virus, developed by the Molecular Virology Laboratory and currently applied in the diagnosis and monitoring of patients in the states of Rondônia and Acre.

"The arrival of these two patients sparked an alert for us to investigate the circumstances of transmission and the possible factors involved in the spread of the disease, considering the family context in which these cases arose and the fact that Lábrea is an endemic region for Delta hepatitis. So we decided to extend the screening to other locations," says Deusilene Vieira.

 The researcher emphasizes that the molecular method fills a significant gap in the discovery of new cases of Delta hepatitis in the Amazon. And, consequently, in screening and following up on patients, since the public network only offers viral load tests for hepatitis B, and the serological tests available on the SUS only show whether the person has had contact with the virus, without informing the current viral load and whether the virus is replicating in the body, which is extremely important for determining the appropriate clinical management for the patient.

Health challenges in riverside communities

In the midst of health challenges, logistical factors and the distance between riverside communities and reference centers further aggravate the population's access to specialized care and the Unified Health System (SUS). For Keyth Ellen, manager of the Rapid Testing and Counseling Center and coordinator of the HIV, syphilis and viral hepatitis programs in Lábrea, the biggest concern today is to offer quality follow-up to chronic hepatitis carriers.
 
The trip from Lábrea to Manaus takes 30 hours on the BR-319 highway, a journey which can take up to five days by boat. The municipality does not have an infectious disease doctor, nor does it have an adequate laboratory structure to carry out more specific tests, which ends up making it difficult to monitor cases of Delta hepatitis. However, "through this partnership with Fiocruz Rondônia, we have been able to access patients, find out the viral load of chronic carriers and offer more humanized follow-up, according to the needs of each case," emphasizes Keyth. She further argues that she hopes to soon be able to see the technology developed by Fiocruz Rondônia incorporated into the SUS, which will be able to meet the needs of other communities.

Part of the work carried out in Lábrea by the Fiocruz Rondônia team focused on training health professionals. In the last action, doctors, nurses and technicians took part in a training course on viral hepatitis, given by researchers Eugênia de Castro and Deusilene Vieira. During the training, the professionals were able to clarify doubts and share experiences and daily challenges in the SUS routine.