Respiratory viruses have been a concern for weeks, and not just because of decisions by the Ministry of Health ministry of health Masks will be mandatory in medical centers until incidence rates start to drop, but also because this year, Influenza increases in intensity Compared to previous seasons.
The latest data released by the Carlos III Health Institute show that the proportion of positive samples is 41%. Although it has dropped from the previous week, it has Transmission rate is very high Relevant to influenza epidemics before and after the coronavirus pandemic.
different influenza viruses
There isn’t just one type of influenza virus. Up to four – A, B, C and D-. The latter only affects animals, while C affects both animals and humans, but is very rare. Every year the epidemic is caused by A and B, Ángela Domínguez, Professor of Preventive Medicine and Public Health at the University of Barcelona, explains to EFEsalud.
caused by virus Influenza A There are two subtypes: N1H1The swine flu pandemic that caused the 2009-2010 flu season was composed of a combination of fragments of genetic material from swine, avian and human viruses; another Type A H3N2emphasize The expert is also the coordinator of the vaccination working group of the Spanish Epidemiology Society (SEE)
The most prevalent type this season is type A, especially the N1H1 subtype.
The B virus also spreads, but to a lesser extent than the A virus. The truth is, “Domínguez insists that when we talk about the spread of influenza viruses, we’re not just talking about one virus, but there may be several subtypes and types that are circulating.”
SARS-CoV-2 is quite stablealthough it is still present and the incidence of respiratory syncytial virus is beginning to decrease.
of the virus that causes influenza bthere are two genealogies, one is no longer circulated, that is Yamagata the other is victory.
symptom
It is difficult to tell what type of influenza virus it is from the symptoms because It depends a lot on the characteristics of the personAs a professor from the University of Barcelona points out.
“In principle, influenza A, especially the H1N1 subtype, could be more severe than influenza B, but that depends on a lot of factors. You can’t say one subtype is more serious than another, because that also depends on The season and the strains that are circulating,” he noted.
The symptoms are similar and the differences are irrelevant. We’re talking high fever, sore throat, headache, muscle and joint pain, and nasal congestion.
Also very similar to COVID-19, although the latter may cause loss of smell and taste. Additionally, fever is not always present.
For older adults and people with chronic medical conditions, it can have more severe effects and may trigger pneumonia. It also affects the nervous system and causes encephalitis, and the heart muscle and causes myocarditis.
The best shield is a vaccine
For prevention, there is the best shield, and that is the vaccine, which is Four pricesthat is, it protects against influenza A and B and their respective subtypes and lineages (N1H1, N3H2, Yamagata and Victoria).
as highlighted Go to EFEsalud Secretary of the Spanish Society of Virology (SEV), Director of the World Health Organization Influenza Center, Director of the Respiratory Viruses Laboratory of the National Microbiology Center of Inmaculada Casasthe flu vaccine changes every year, depending on what viruses were circulating last season.
“At the World Health Organization Influenza Center, what we do is find out how different the influenza that is circulating is from the strains of influenza or vaccines that are given to the population. There is always a ratio or variation. Now we are doing these types of studies , the most widespread of which is N1H1, which is present in vaccines,” Casas explained.
However, he said there is not yet precise enough data on how many genes and antigen groups are in circulation to prepare a vaccine for next season.
To analyze and decide on the vaccines needed for the next season, WHO laboratories met in Geneva at the end of February.
“This virological knowledge is used to decide whether the virus needs to be changed based on the vaccines that are administered in the population this year,” Casas explained.
Vaccine type
as he explained Go to EFEsalud Pediatrician Fernando Moraga-Loppe, spokesman for the Spanish Vaccinology Associationthere are two main types of vaccines: inactivateds (from dead viruses) and by injection and those attenuated virusthat is, inside the nose.
Attenuated viruses contain viruses that have been modified in the laboratory to make them less effective. Neither type causes the disease in healthy people, but they still retain the ability to stimulate antibody production.
Moraga-Llop clarified that regarding Europe’s intranasal vaccine, it is specifically intended for children and adolescents aged 2 to 17 years. It has a wider range of indications in the United States.
Recommended to whom?
according to Interregional Commission on National Health Systems (CISNS) Current recommendations Premature and at-risk children should be vaccinated.
In addition, systemic vaccination for children aged 6 to 59 months was approved last October.
health authorities believe There are also risk groups arrive:
- people Over 60 years old.
- Pregnant and postpartum women.
- People under 60 with the following risk conditions: Chronic cardiovascular, neurological, or respiratory disease, including bronchopulmonary dysplasia, cystic fibrosis, and asthma; diabetes; chronic kidney disease and nephrotic syndrome; chronic liver disease, including chronic alcoholism; severe neuromuscular disease; and immunosuppression .
- Can spread the flu to people who are at high risk for complicationssuch as nursing staff.
- Other groups recommended for vaccination: They are smokers, health personnel, security forces, firefighters and workers in essential public services such as civil protection.
Even though it’s January and vaccination campaigns begin in early fall, Moraga-LLop said you have to get vaccinated while the virus is circulating.
The vaccine becomes effective fifteen days after vaccination.
supporting measures
But in addition to vaccines, there are other well-known complementary measures to avoid contagion: masks, hand hygiene, and ventilation of confined spaces.
For the SEV Secretary, the use of masks in health centers is necessary until the incidence of respiratory viruses starts to decrease, following the decision of the Ministry of Health.
“They told me one day that there were a lot of people in the emergency room at a hospital, and a lot of them had respiratory symptoms. Masks could somehow control the spread of these respiratory viruses that spread very easily. It doesn’t matter when the emergency room is full. Not because they are in good health and obviously the vulnerable must be protected,” Immaculada Casas said.
He noted that its special use was justified due to the occurrence of respiratory viruses such as influenza, and that obviously it should not be worn in August or when the situation normalizes.
The SEE Vaccine Group Coordinator also expressed the same idea, because although the vaccine is the “most important” prevention technology among all existing prevention technologies, “it is not a foolproof technology”, so care must be taken. This includes the use of masks.