Developed with the participation of the Oswaldo Cruz Institute (IOC/Fiocruz), the first molecular diagnosis kit for rotavirus and norovirus in Brazil should contribute to pathogen surveillance and investigation of acute diarrhea outbreaks. 

The innovation was approved by the National Health Surveillance Agency (Anvisa). The quadriplex test allows four simultaneous investigations, including rotavirus, two norovirus genogroups and an internal control, which increases the reliability of the results.  

The kit was developed by the Paraná Institute of Molecular Biology (IBMP) in partnership with the three reference laboratories for rotaviruses in the country, based on a demand from the General Coordination of Public Health Laboratories of the Ministry of Health (CGLAB/MS). 

O IOC participated in the development of the test through the Laboratory of Comparative and Environmental Virology, which acts as a regional reference for rotaviruses together with the Ministry of Health and the World Health Organization (WHO). 

The regional reference laboratory of the Adolfo Lutz Institute (IAL) and the national reference laboratory of the Evandro Chagas Institute (IEC) also participated. 

Experts highlight the importance of the test for public health, considering that noroviruses and rotaviruses are the main viruses that cause acute diarrhea in Brazil and worldwide, with an impact mainly on the health of children under five years of age and the elderly, who are more vulnerable to the disease. 

“The kit will allow for faster diagnosis in cases of acute diarrhea. This is important during outbreaks, to adopt control measures and, in the context of surveillance, to detect changes in the transmission of these viruses early. It also helps to monitor the effectiveness of vaccination against rotavirus, which has significantly reduced infections in Brazil, protecting children from severe cases of diarrhea caused by this agent,” says the coordinator of the Regional Reference Laboratory for Rotaviruses of the IOC, Tulio Fumian. 

“The kit allows for methodological standardization in the country’s laboratories, making results more comparable. Furthermore, it is produced with 100% national inputs, which strengthens knowledge and technology ownership in Brazil,” highlights IBMP’s in vitro diagnostics coordinator, Irina Riediger. 

Molecular diagnosis of rotavirus and norovirus is based on the detection of the genetic material of the pathogens in stool samples. 

Currently, the country's three reference laboratories perform this detection using their own methodologies, called “in house”, using inputs from different suppliers. 

The new diagnostic kit standardizes the methodology and brings together all the necessary inputs for the exam, with national reagents produced by IBMP. 

The coordinators of the reference laboratories provided scientific advice for the development of the kit, which underwent two rounds of validation tests, the first at IBMP, which manufactured the product, and the second at the reference laboratories.  

“With the in-house methodology, three separate tests are performed, one for rotavirus and two for norovirus. With the kit, the three tests are performed at once and the internal control indicates whether the RNA extraction procedure was performed correctly. This greatly speeds up the performance of the tests and provides greater reliability for the results generated,” explains the deputy coordinator of the Regional Reference Laboratory for Rotaviruses at IOC, Fernanda Burlandy. 

The test took about two years to develop. With Anvisa's approval, the kit can be sold. 

The adoption of technology in the Unified Health System (SUS) depends on an assessment by the National Commission for the Incorporation of Technologies in the SUS (Conitec) and a decision by the Ministry of Health. 

According to experts, carrying out the test in the Central Public Health Laboratories (Lacens) of the states can further speed up the diagnosis of infections. 

“Today, all states need to send samples to reference laboratories to obtain molecular diagnosis. With the kit, we will be able to train Lacens to perform this test, offering a faster diagnosis,” comments Tulio. 

Public health problem

Acute diarrhea is a serious public health problem. According to the World Health Organization (WHO), it is the third leading cause of death in children under five years of age worldwide. 

Infections by viruses, bacteria and other parasites are among the most common causes of the disease.  

Laboratory diagnosis is important to identify the microorganisms circulating in each location, to guide control measures when outbreaks occur and to monitor the effectiveness of vaccination against rotavirus.  

In Brazil, most cases of diarrhea caused by viruses are associated with noroviruses, since rotavirus infections fell after the introduction of the vaccine in 2006. 

On the international scene, the impact of the vaccine was confirmed in study with participation of IOC. Based on monitoring of 28 countries in the Americas, Africa, Europe, Asia and Oceania, the study found that rotaviruses are responsible for 33% of hospitalizations due to diarrhea in children under five years of age. The rate drops by half where there is immunization. 

In addition to vaccination, access to drinking water and adequate sanitation conditions, as well as hygiene habits, are important measures to prevent infections.