RSV Climbs for Five Straight Weeks in Puerto Rico: 62 Cases in Week 42, 1,275 So Far in 2026

Respiratory syncytial virus (RSV) is not letting up in Puerto Rico. Epidemiological week 42 (October 18 to 24) recorded 62 cases, a 51.2% jump from 41 the week before, and that makes five consecutive weekly increases, according to Health Department surveillance published October 30 ¹. The surge comes just as families are talking about influenza, COVID-19 and seasonal shots, while RSV rarely gets the same attention even though it hits the youngest children hardest.

Background: a virus that eats into kids' winters

RSV affects the lungs and airways. It starts like a common cold, with cough, nasal congestion and fever, but in babies, young children and older adults it can lead to bronchiolitis, pneumonia or hospitalization ¹. It spreads through coughing, sneezing, direct contact or touching contaminated surfaces, and most patients recover in one to two weeks ¹.

In April, when Health presented its respiratory illness update, the year-to-date total stood at 725 cases and 281 hospitalizations, with no associated deaths ². The counter has kept climbing since then, and this fall's picture shows the circulation season has not ended but is reactivating.

The numbers

• Week 42 (October 18 to 24): 62 cases, 51.2% more than the 41 in week 41 ¹.
• 2026 year to date: 1,275 cases, 512 hospitalizations and one death associated with the virus ¹. That means roughly 40 of every 100 reported cases ended in hospitalization, a high share that reflects how heavily this virus weighs on pediatric wards.
• Children under 5: 1,019 cases, about 80% of the total ¹.
• October versus September: 153 cases through October 24, compared with 88 in all of September ¹.
• Where it hits hardest: the regions with the highest cumulative incidence are Mayagüez, Metro, Bayamón and Caguas. At the municipal level, Arroyo leads with a rate of 93.7 per 100,000 residents, followed by Maricao, Guayama, Dorado and Aibonito ¹.
• Point of comparison: between April, when 725 cumulative cases were counted ², and week 42, the total rose by 550 cases, and hospitalizations went from 281 to 512 ¹².

One caveat: these are cases reported to surveillance, not the full universe of infections. Many mild infections are never tested, so actual circulation is higher.

What it means for you

If you have children under five, this is the group where the virus concentrates, and October has already far surpassed September ¹. If you live in Arroyo, Maricao, Guayama, Dorado or Aibonito, or in the Mayagüez, Metro, Bayamón or Caguas regions, your area is among those with the highest incidence ¹. If you care for an older adult, remember that older adults also face a risk of complications ¹.

The warning signs in children, according to Health, are trouble breathing, persistent fever and signs of dehydration ¹. If any of them appear, do not wait: seek medical care.

There are prevention tools beyond handwashing. The CDC recommends the RSV vaccine for all adults 75 and older and for adults 50 to 74 at increased risk of severe disease ³. For babies, it recommends one of two routes: the maternal vaccine (Pfizer's Abrysvo) during pregnancy or an RSV antibody given to the baby after birth ³. Talk to your obstetrician or pediatrician about which applies to you.

How to / Checklist

1. Step up handwashing at home, daycare and school, and avoid close contact with sick people ¹.
2. Stay home if you or your kids have respiratory symptoms, and avoid sending a baby to daycare with a cough or fever ¹.
3. Watch for warning signs in children: trouble breathing, a fever that will not break and dehydration. If they appear, go to a doctor or an emergency room ¹.
4. Ask about RSV protection with your pediatrician or obstetrician: the maternal vaccine during pregnancy or the antibody for the baby ³.
5. If you are 75 or older, or 50 to 74 with a risk condition, ask your doctor about the RSV vaccine ³.
6. Use the visit to catch up on influenza. If the person is bedridden or has limited mobility, Health's vaccination program is coordinated at 787-522-3985 ².
7. Check current data at www.salud.pr.gov/vigilancias or call the Health Department main line, 787-765-2929 ².

What's next

Health updates its surveillance reports weekly, so the next bulletins will show whether week 43 and beyond keep the streak of increases or the virus levels off ¹. With five straight weeks of growth and October already above September, more cases are likely before the curve flattens, and that is exactly what puts pressure on pediatric wards. The advice for families does not change: basic prevention, early care and a conversation with the doctor about immunization options before the virus reaches your home.

Sources

1. Metro Puerto Rico, "Repuntan los casos de virus respiratorio sincitial en Puerto Rico," November 5, 2026, with data from the Health Department epidemiological surveillance report of October 30.
2. Puerto Rico Department of Health, "Secretario de Salud actualiza datos sobre enfermedades respiratorias y arbovirales," April 22, 2026.
3. Centers for Disease Control and Prevention (CDC), RSV vaccines.