As Costa Rica enters its rainy season, a marked increase in respiratory virus infections has been observed, notably earlier than in previous years.

Typically, cases and hospitalizations begin to rise by late May or early June, but this year, the uptick started around mid-April and has remained consistent.

Hospital officials report a significant increase in influenza cases, with José Antonio Castro Cordero, an infection committee member at Mexico Hospital, noting that the peak for influenza has occurred earlier than expected.

In response to the alarming situation, Mexico Hospital, along with others such as Calderón Guardia and San Juan de Dios, has mandated the wearing of masks within their facilities.

The National Children's Hospital (HNN) has also reported eleven fatalities attributed to respiratory viruses so far this year.

The circulation of respiratory viruses has surged over the past month.

Data indicates that while the rhinovirus was previously the most common, it has now declined, allowing for the spread of more severe pathogens such as influenza and SARS-CoV-2, the virus responsible for COVID-19. According to the Costa Rican Social Security Fund (CCSS), influenza infections account for over half (52.3%) of cases among those infected with respiratory viruses.

As of May 3, statistics from the Ministry of Health reveal there were 5,349 cases of severe acute respiratory infections (SARI) reported in the first 18 weeks of the year, predominantly affecting children under five years old and adults over 75. The incidence of these illnesses is especially pronounced in northern and southern regions of the country, with lower rates reported in the Caribbean.

In addition to severe infections, 541,793 cases of upper respiratory infections (URIs) have been reported, mainly affecting children under nine years old.

The flu-like illness has also seen an increase, with 7,366 cases documented up to this point in the year.

The COVID-19 situation remains dynamic, with 155 cases reported in week 19, marking a 70% increase compared to the previous week.

There were 17 hospitalizations recorded at that time, including one in intensive care, reflecting a 21% rise within a week.

The CCSS's Technical Report on the Behavior of Influenza Virus and other respiratory viruses noted a 34.46% increase in respiratory virus cases since week 17, which ended on April 26.

At the National Children's Hospital, the pediatric ward's occupancy rate stood at 73.13%, indicating stability but not saturation.

Hospital director Carlos Jiménez Herrera reported an increase in admissions for respiratory syncytial virus (RSV), which poses significant risks for infants.

Notably, the serious cases that resulted in fatalities had underlying health issues, with six of the deceased being under one year old, three aged one to four years, and two aged ten to fourteen.

Respiratory viruses are primarily transmitted through respiratory droplets, which can be expelled when an infected individual coughs, sneezes, or speaks.

The transmission dynamics of COVID-19 involve aerosol spread, where virus particles remain suspended in the air.

Preventative measures recommended include ensuring vaccination is up to date, favoring well-ventilated spaces, and maintaining hygiene practices such as frequent handwashing.

In the event of respiratory virus symptoms, individuals are advised to limit contact with vulnerable populations and wear masks in public settings.

Additional guidance emphasizes the importance of seeking medical consultation if symptoms persist or worsen and the significance of resting and staying hydrated during recovery.