Since the beginning of August, Brazil has been recording an increase in cases of influenza B, the virus that causes the flu. According to reports on flu syndromes from the Ministry of Health, while at the end of July this pathogen had an almost insignificant participation in the records of Severe Acute Respiratory Syndrome (SARS), in the most recent bulletin, released on October 25th, it already responded for 12% of cases and 13% of deaths. It currently ranks second in deaths from SARS, behind only the Covid-19 virus.
The increase has been constant over the last two months. In August alone, the rate of cases and deaths practically doubled, going from around 2% in the first days to 5% and 4%, respectively, at the end of the month. You Ministry of Health records also highlight an increase in the detection of this pathogen in October, with growth in the Southeast and South regions.
The good news is that a decline has begun to be observed in private laboratories. Numbers of these establishments compiled in monitoring carried out by the Todos pela Saúde Institute (ITpS) show that the positive rate jumped from 3.13% at the beginning of August to 21.55% at the end of September. The latest report, dated October 18th, shows a small drop, reaching around 18%.
Even so, alongside rhinovirus, influenza B is the main respiratory virus currently circulating, according to ITpS. Covid-19 represents 8.03% of positive results; that of Influenza A accounts for 4.5%; and Respiratory Syncytial Virus (RSV), 0.9%.
The emergence of these viruses at this time of year is surprising, as they usually peak at the beginning of autumn and winter. “There is a temperature factor, as this year we had fewer cold periods”, assesses infectious disease specialist Emy Akiyama Gouveia, from Hospital Israelita Albert Einstein.
The influenza virus is transmitted through secretions or droplets when coughing, talking or sneezing; and also through contact with contaminated surfaces. Greater crowding indoors due to the cold favors this spread.
A change in seasonality was also observed in December 2021, when there was an unexpected increase in flu and RSV cases in the summer.
Low vaccination adherence
But it’s not just seasonal factors that influence recent flu spikes. “There is also the issue of low adherence to the vaccine, as this influences these unexpected cases, at different times”, says Gouveia.
Until October 25th, flu vaccination had reached only half (52%) of the target audience, which includes children, pregnant women, postpartum women and the elderly. “It is worth remembering that antibodies after vaccination last, on average, from six to 12 months and that is why it is necessary to take the vaccine every year”, emphasizes the doctor.
The flu vaccine protects against types of influenza A and B and is available in the Unified Health System (SUS) and in the private network. In an email sent to Agência Einstein, the Ministry of Health reinforces the importance of flu vaccination to reduce hospitalizations and deaths from influenza.
Symptoms of influenza B
Symptoms of the flu caused by this agent include fever, chills, sore throat, headache, muscle pain, cough, runny nose, fatigue and even vomiting and diarrhea, in some cases.
Most people recover in about two weeks, but some may experience complications, such as pneumonia. Shortness of breath, respiratory discomfort, low blood pressure, worsening general condition are warning signs of the worsening of the disease and possible progression to SARS.
Anyone who has these symptoms should rest and increase hydration. Medications that do not require a prescription, such as antipyretics, can be used according to medical advice. Another recommendation is to wear a mask to prevent the spread of the virus.
Those who have risk factors for complications from influenza — pregnant and postpartum women, the elderly, children under 5 years of age, people with certain lung, heart, kidney diseases, diabetes, immunosuppressed people, among others — should be monitored more closely and may be recommended a antiviral right from the start. Anyone who shows signs of worsening should seek medical attention.
This content was originally published in Influenza B cases show an atypical rise for the season on the CNN Brasil website.
Source: CNN Brasil
I am an experienced journalist and writer with a career in the news industry. My focus is on covering Top News stories for World Stock Market, where I provide comprehensive analysis and commentary on markets around the world. I have expertise in writing both long-form articles and shorter pieces that deliver timely, relevant updates to readers.
