A healthy carrier of the Covid virus is positive during the screening test but does not show any symptoms of the disease. Contagious, it can infect those close to it. Definition, duration, test, isolation: advice for healthy carriers.
You can be infected with the Sars-Cov-2 virus from Covid but be asymptomatic. In other words, the person has no symptoms but can still transmit the virus and contaminate the surroundings. We then speak of “healthy carrier”. Is this the same as an “asymptomatic” case ? How do you know if you are a healthy carrier of a virus? During how long are you contagious ? What is the typical profile of a healthy carrier of Covid-19 ? What to do ? Isolate or not?
What is the definition of healthy carrier?
A healthy carrier is a person whose body is infected with an infectious agent (virus, bacteria, parasite) but who does not show clinical signs of this infection. In other words, he carries the infectious agent in his system without being sick. On the other hand, a healthy carrier can transmit the infectious agent to other people with whom he is in contact. A healthy carrier is therefore contagious.
What diseases can you be a carrier of?
You can be a healthy carrier of different viruses and diseases: chickenpox, flu, hepatitis B, tuberculosis, STDs such as chlamydia, HIV (AIDS) and herpes… We can also be healthy carrier of a gene as is the case with certain genetic and therefore non-contagious diseases (Cystic fibrosis for example). In this case, the genes are transmitted from the parents to their child. Every child inherits half of their genes from their father and the other half from their mother. In France, more than two million people are carriers of the cystic fibrosis gene without knowing it: these are called “healthy carriers”. They have a risk of transmitting the gene for the disease to their child, without however developing the disease, specifies Orphanetthe information portal dedicated to rare diseases.
What is the difference between a healthy carrier and an asymptomatic one?
These two concepts have substantially the same definition. A healthy carrier and an asymptomatic person have both been infected but do not show clinical symptoms associated with the infection. Small subtlety however:
- We speak of a “healthy carrier” for an infectious disease (healthy carrier of a virus for example) or a genetic disease. On the other hand, we cannot speak of a “healthy carrier” for a metabolic disorder (diabetes, arterial hypertension, etc.).
- We speak of an “asymptomatic” person for an infectious disease, a genetic disease or for metabolic disorders
To diagnose an asymptomatic person with Covid, we cannot rely on the presence of symptoms. Thus, the only way to know if you are a carrier of Covid-19 (with or without symptoms) is to look for the presence of the virus, thanks to the realization ofa PCR test (a sample taken from the nose using a cotton swab) which makes it possible to diagnose possible contamination with Covid-19. If a person is infected with the coronavirus at the time of the sample, the PCR test will detect it.
► If the test is negative, we deduce that the person is not a carrier of the virus
► If the test is positivewe deduce that the person is a carrier of the virus and is therefore contagious.
• If the positive person has no symptoms at the time of the sample, it is said to be a healthy carrier.
• If the positive person has symptoms (fever, cough, loss of smell, etc.), they are said to be symptomaticit is not a healthy carrier.
► Warning : there are “false negatives“may be due to poor sampling technique.
What to do if you are a healthy carrier of Covid?
A healthy carrier is positive for the Covid virus and must therefore follow the same recommendations as symptomatic cases: she has to isolate herself for 7 days if her vaccination schedule is complete (2 doses + 1 booster or 1 Covid + 2 doses) or 10 days if she is not vaccinated against Covid or has not done her boosters.
Are we contagious when we are a healthy carrier?
The healthy carrier has no symptoms but stay contagious. He can therefore transmit the disease to other people. In December 2020, the Covid Scientific Council indicated that asymptomatic cases were responsible for approximately 40 to 50% of new infections.
What is the duration of contagion of a healthy carrier?
There are no hard data to answer this question. However, remember that the average duration of contagion of a Covid-positive case is set at one week. It can then vary depending on the case, as indicated the president of Covars, Brigitte Autran, on October 10, 2022 on France Inter: “The viral load varies enormously depending on the severity of the disease and the symptomatology. We do not excrete the same quantities of virus if we have a virus that infects the nose rather than the throat. Of course there is a proportionality between the number of viral particles that we produce and the number of contaminations what we might do.”
Does a healthy carrier have antibodies against Covid?
Nothing proves it. Nevertheless, a first infection with Covid-19 would lead to some form of protection against the virus in the vast majority of cases. Even if reinfections are quite possible.
Why are some of us carriers?
A healthy carrier of a virus does not present any clinical manifestation of the infection:
- either because the infectious agent (virus, bacteria, etc.) is not very virulent : the agent is too weak to cause reactions in the body and therefore symptoms.
- either because its immune defenses are very effective (it develops more antibodies than the average) and prevent the appearance of symptoms.
Sources: COVID-19 rapid summary. Share of asymptomatic forms and transmission of SARS-CoV-2 in the pre-symptomatic phase. Saint-Maurice: Public Health France, July 8, 2020 / Epidemiological points of Covid-19 weekly, Public Health France.