Increase in respiratory infections in Argentina: what the latest data say and what viruses are circulating

Outpatient Monitoring Units in Argentina recorded an increase in influenza cases between weeks 16 and 23 of 2024. This upward trend declined starting in week 24.

The Ministry of Health released data on respiratory infections in Argentina. Between weeks 16 and 23 (mid-April and early June), a significant rise in influenza cases was observed, with a decrease in cases reported from week 24 (mid-June). Weekly cases remained high, exceeding 1,000 between weeks 22 and 24 (late May and early June).

There has been a gradual increase in respiratory syncytial virus (RSV) detections, with over 700 cases registered in the last four weeks. Week 26 of 2024 also saw circulation of SARS-CoV-2, metapneumovirus, adenovirus, and parainfluenza.

Between weeks 1 and 26 of 2024, 562,526 cases of ILI (Influenza-Like Illness), 73,289 cases of Pneumonia, and 64,907 cases of Bronchiolitis were recorded in children under two years of age. This represents a decrease in notifications of -2.64% for ILI, -23.64% for pneumonia, and -49.05% for bronchiolitis compared to the same period in 2023. In the first 27 weeks of 2024, 105 deaths were reported in people diagnosed with influenza.

Outpatient Monitoring Units observed an upward trend in influenza cases between weeks 16 and 23. From week 24 onward, a lower number of weekly detections were verified, with 21 positive cases out of 68 samples studied in the last week. Additionally, one case of SARS-CoV-2 was recorded among 503 samples analyzed by molecular technique in week 27. In the past two weeks (26 and 27), 21 positive RSV cases were detected among 133 samples studied.

In week 27 of 2024, 51 confirmed cases of COVID-19 were recorded, along with one death attributed to this diagnosis. Previously, between week 52 of 2023 – August – and week 4 of 2024, an increase in COVID-19 cases was verified. In week 4 of 2024, the number of cases surpassed the peak recorded during the last surge in the second half of 2023 (SE35), followed by a subsequent downward trend.

Regarding hospitalized cases, week 27 of 2024 saw 17 SARS-CoV-2 detections, 70 influenza cases, and 245 RSV cases. Between weeks 16 and 23, influenza detections showed an upward trend, with a lower number of weekly notifications since week 24. From week 16 of 2024, an upward trend in RSV cases was observed. SARS-CoV-2 detections remain at low levels.

Respiratory syncytial virus (RSV) is a leading cause of lower respiratory infections in infants and young children. It causes infections such as bronchiolitis and viral pneumonia. Argentina has numerous therapies to combat RSV.

RSV spreads through respiratory secretions (droplets) dispersed when infected individuals cough or sneeze, as well as through direct contact. Every year, during the autumn and winter months, there is an increase in RSV circulation, leading to more outpatient pediatric visits and hospitalizations, particularly in children under one year of age and older adults.

Pablo Bonvehí, head of the Infectology section of CEMIC and member of the Vacunar Foundation, emphasized the importance of prevention measures like using and disposing of disposable tissues, frequent handwashing, and proper ventilation. Pulmonologist Diego Litewka, head of Pulmonology at the Juan A. Fernández Hospital, highlighted that infected individuals often spread the virus between three and eight days following symptom onset. Due to underdiagnosis, precise epidemiological data, especially in adults, is limited.

RSV can cause harm at all stages of life. Vaccinations are essential to prevent severe cases. The Pfizer RSV vaccine for pregnant women, included in the National Vaccination Calendar, is administered free of charge and is mandatory between weeks 32 and 36 of pregnancy. It provides regarding 6 months of protection for newborns through maternal antibodies.

The Pfizer vaccine for pregnant women was approved by ANMAT in September 2023 and included in the National Vaccination Calendar by the Ministry of Health in December. The vaccination campaign began in March of this year to protect pregnant women and their unborn babies.

Vaccines are now available in Argentina to protect vulnerable groups from RSV. GSK and Pfizer offer two therapeutic options to counteract the virus’s effects in older adults. The Food and Drug Administration (FDA) in the United States authorized the RSV vaccine developed by Moderna for adults aged 60 or older in late May 2024. While not yet authorized in Argentina, this approval sets a precedent for regulatory agencies worldwide. Moderna is also researching three vaccines in Phase III trials aimed at protecting the population once morest “tripledemia” (COVID-19, RSV, and influenza).

Moderna also reported data from a trial this week for a combined vaccine for COVID and influenza, called ARNm-1083. The combined vaccine is expected to be available in 2025. The most recent therapeutic tools available in Argentina are designed to protect those over 60 years of age. Two major laboratories have launched vaccines for this age group in recent months. The GSK vaccine demonstrated 82.6% efficacy in preventing lower respiratory infections caused by both RSV A and RSV B in this population, and 94.6% efficacy in adults with chronic diseases.

GSK’s vaccine is approved for people over 60 years of age in Argentina. This week, the Food and Drug Administration (FDA) authorized the GSK RSV vaccine for at-risk adults between 50 and 59 years of age. The Pfizer RSV vaccine, part of Argentina’s National Immunization Schedule, is available for free to pregnant women between weeks 32 and 36 of pregnancy. It is also available at vaccination centers for adults over 60 years of age, according to medical advice.

Influenza Cases Surge in Argentina: Outpatient Monitoring Units Report Upward Trend

Argentina experienced a significant increase in influenza cases between weeks 16 and 23 of 2024, according to data released by the Ministry of Health. The Outpatient Monitoring Units (OMUs) reported a sharp upward trend in influenza detections during this period, with fewer cases reported from week 24 onwards.

The Ministry’s latest Epidemiological Bulletin revealed that the respiratory virus network identified a substantial rise in influenza detections, with over 1,000 weekly cases reported between weeks 22 and 24. While the number of influenza cases has declined since week 24, the incidence remains at high levels.

Respiratory Syncytial Virus (RSV) on the Rise

In addition to influenza, the Ministry of Health reported a gradual increase in respiratory syncytial virus (RSV) detections, with over 700 cases registered in the last four weeks.

The circulation of other respiratory viruses, including SARS-CoV-2, metapneumovirus, adenovirus, and parainfluenza, was also detected in week 26 of 2024.

Influenza Cases by the Numbers

The Ministry of Health provided detailed statistics on respiratory infections in Argentina, including:

• ILI (Influenza-Like Illness): 562,526 cases reported between epidemiological weeks 1 and 26 of 2024, representing a decrease of -2.64% compared to the same period in 2023.
• Pneumonia: 73,289 cases reported in children under two years of age between weeks 1 and 26 of 2024, representing a decrease of -23.64% compared to the same period in 2023.
• Bronchiolitis: 64,907 cases reported in children under two years of age between weeks 1 and 26 of 2024, representing a decrease of -49.05% compared to the same period in 2023.
• Influenza-related Deaths: 105 deaths reported in the first 27 weeks of 2024.

COVID-19 Cases Remain at Low Levels

While the number of COVID-19 cases has declined, the Ministry of Health reported 51 confirmed cases in week 27 of 2024, along with one death.

Hospitalization Trends

Hospitalized cases showed the following trends in week 27 of 2024:

• SARS-CoV-2: 17 detections
• Influenza: 70 cases
• RSV: 245 cases

RSV: A Leading Cause of Respiratory Infections

Respiratory syncytial virus (RSV) is a significant cause of lower respiratory tract infections, particularly in infants and young children. The virus can also affect older adults, leading to serious complications.

Prevention and Vaccination

Experts emphasize the importance of preventive measures to protect once morest RSV, including:

• Using and disposing of disposable tissues
• Frequent handwashing
• Proper ventilation of rooms

Vaccines offer crucial protection once morest severe RSV cases. In Argentina, the Pfizer RSV vaccine is available for pregnant women between weeks 32 and 36 of pregnancy. Several vaccines are also available for adults over 60 years of age, with GSK and Pfizer offering therapeutic tools in the country.

Other Respiratory Viruses

The Ministry of Health continues to monitor the circulation of other respiratory viruses in Argentina, including COVID-19, influenza, and RSV. Vaccination and preventive measures remain essential to protect public health.

As the respiratory virus season progresses in Argentina, the Ministry of Health will continue to monitor the situation closely and provide updates on the incidence of respiratory infections.