By Osehobo Ofure
The U.S. Department of State and U.S. Centers for Disease Control and Prevention (CDC) this week reminded all travelers that beginning from January 26, 2021, all air passengers two years of age or older arriving to the United States must provide proof of a negative COVID-19 test or proof of recovery from COVID-19 before boarding.
Nigeria has a similar regulation in place. It says that passengers must perform a COVID-19 PCR test not more than 4 days (96 hours) before boarding. PCR tests done more than 96 hours before departure are not valid and persons will not be allowed to board. Test validity commences from the time the sample is taken. For passengers with multiple connections before arrival in Nigeria, the 96-hour test validity is from the first point of departure.
Secondly, it says that all intending passengers (including diplomats and children less than 10 years old) must register via an online national travel portal and proceed to fill in the online Health Declaration/Self-Reporting form located on the portal.
They are also to ensure that the information/contact details provided on the form are correct and verifiable. Passengers must also be reachable via the phone number, email and residential address they have provided. In addition, the passengers are required to inform Port Health officials on arrival of any change in their health circumstances since completion of the Health Declaration/Self-Reporting Form. Passengers who falsify their status as diplomats will face prosecution.
After filling the online Health Declaration/ Self-Reporting Form, the NCDC says passengers will be directed to upload their negative COVID-19 PCR test on to the portal. Once this is successfully done, they will proceed to the payment section of the travel portal. Passengers are advised to still bring along an electronic or hard copy of their COVID-19 PCR test for presentation at the airport.
For the avoidance of doubts, the US Center for Disease Control and Prevention has two approved kinds of tests. They are the COVID-19: viral tests and antibody tests.The center says that a viral test tells you if you have a current infection while an antibody test might tell you if you had a past infection. It does not talk of a negative test.
Experts say a diagnostic test can show if one has an active coronavirus infection and should take steps to quarantine or isolate yourself from others. They say currently there are two types of diagnostic tests– molecular tests, such as RT-PCR tests, that detect the virus’s genetic material, and antigen tests that detect specific proteins from the virus.
An antibody test looks for antibodies that are made by our immune system in response to a threat, such as a specific virus. Antibodies can help fight infections. Since antibodies can take several days or weeks to develop after an infection and may stay in the blood for several weeks or more after recovery, they say antibody tests should not be used to diagnose COVID-19.
The NCDC insists on polymerase chain reaction (PCR) and antibody testing. These are the dominant ways that global healthcare systems are testing citizens for Covid-19.
PCR testing can detect the genetic information of the virus, the RNA. That’s only possible if the virus is there and someone is actively infected. The PCR tests are used to directly detect the presence of an antigen, rather than the presence of the body’s immune response, or antibodies. By detecting viral RNA, which will be present in the body before antibodies form or symptoms of the disease are present, the tests can tell whether or not someone has the virus very early on.
Again experts say that PCR tests can be very labour intensive, with several stages at which errors may occur between sampling and analysis. They say false negatives can occur up to 30% of the time with different PCR tests, meaning they’re more useful for confirming the presence of an infection than giving a patient the all-clear.
They advise blood samples for antibody tests. This is because there will be a very small amount of the coronavirus circulating in the blood compared to the respiratory tract, but a significant and measurable antibody presence. Again there is an agreement that no test is 100% accurate all of the time.
However in terms of considerations for who should get tested, the US CDC says
people who have symptoms of COVID-19,
people who have had close contact (within 6 feet for a total of 15 minutes or more) with someone with confirmed COVID-19 and people who have taken part in activities that put them at higher risk for COVID-19 because they cannot socially distance as needed, such as travel, attending large social or mass gatherings, or being in crowded indoor settings.
Others are people who have been asked or referred to get testing by their healthcare provider, local or state health department. Essentially therefore one can take a voluntary test if such a person has found himself in any of the situations mentioned. To take a voluntary test would require personal commitment in terms of interest and willingness backed by capacity. This kind of test is needed by people who need to travel abroad and want to meet necessary travel requirements.
Talking of a Negative certificate and proof of recovery from COVID-19, these two are now required to travel to the USA. Yet the CDC says if you test negative, you probably were not infected at the time your sample was collected. The test result only means that you did not have COVID-19 at the time of testing.
So how do you get a Covid19 negative certificate or proof of recovery from COVID-19?For those coming into the USA, they must need to do the tests in their country of departure. The CDC has not said a certificate from another country will be accepted by the US. Chances are that it lay since the criteria for testing for COVID-19 is according to the national case definition. This is anyone with cough and/or fever (or history of fever in the last two weeks) with one or more of known COVID-19 symptoms.
In Nigeria today, the National Center for Diseases Control, NCDC only advises persons who are showing symptoms of COVID-19, to self-isolate and then call their state helpline. The person’s State Ministry of Health supported by NCDC will thereafter arrange for sample collection and communicate the result. What of those without the symptoms? And there are persons who show no symptoms? Can persons without symptoms go for tests voluntarily? Yes especially now they need to travel abroad.
All the information about the procedures to take these tests, who can take the tests, locations, the cost implications of the tests and who bears the costs of the tests and perhaps the average lifespan of a test, to make valid for travel to a place like the United States are in the NCDC guidelines which can be downloaded and read.