Vaccine for Covid-19 (Second part)

A major challenge during rapid development is to avoid safety issues. A syndrome of "disease enhancement" has been reported in the past for a few viral vaccines where those immunized suffered increased severity of infection or death when they later encountered the virus. Since some SARS-CoV-1 vaccines have shown evidence of disease enhancement in some animal models, this is a concern for SARS-CoV-2 vaccines as well. (1)

-Development of vaccines requires constant improvements and for this specific type, scientists relied on previous forms of vaccines for other coronaviruses. To perform in the best possible way, they must find a way to avoid the enhancement of disease, which was an unfortunate circumstance in previous types of vaccines. The first and second trials went well, but the third one includes time spent in the “natural” environment where people could be exposed to cases of Covid-19 without knowing it. Just after that, if contact resulted in infection, scientists could conclude the vaccine's effectiveness. Whether people who were previously vaccinated will or not (over)react to the infection and what will this reaction obtain; time will show the outcome and only then will vaccines be released. 

Below is a short review of some of the medicines which were used for treatment and what were side effects (if any). 

REMDESIVIR 

“Remdesivir, the first authorized COVID-19 antiviral treatment in the EU., was associated with shorter median recovery time compared to placebo (11 vs. 15 days).” (1)

When given remdesivir, patients show a faster recovery rate but side effects could include severe disruptions of the digestive system, constant headaches (different than those caused by Covid-19 solely). The fact that every antiviral drug for treating immunocompromised patients contains specific RNA sequences is enough to understand the possibility of various side effects. Different from natural RNA sequences for the vaccinated organism, these sequences were made to provide protein manufacturing and immunity raising. Considering the wide spectre of human genetics, it is only reasonable to see how different these sequences can interact.

“Pharmaceuticals undergoing clinical trials to assess their safety and efficacy as potential treatments for COVID-19, include the antiviral nucleotide analog remdesivir, systemic interferons and in particular interferon β-1a, the antiviral combination lopinavir/ritonavir, the antimalarial chloroquine/hydroxychloroquine, and monoclonal antibodies against components of the immune system such as interleukin-6 (IL-6) and IL-4 . It is important that the potential treatments are carefully assessed in randomized controlled trials. Based on these findings, the US National Institutes of Health (NIH) recommends the administration of dexamethasone for COVID-19 patients who are either mechanically ventilated or require supplemental oxygen .” 

Convalescent plasma 

Last but not least of a try was convalescent plasma. Despite high hopes, results were not promising so this treatment was rejected by the majority of medical professionals. But still, some chances are given and therefore this plasma, with antibodies from recovered COVID-19 patients is under observation. 

“EU/EEA Members States activities are carried out according to EC guidance developed in collaboration with ECDC, national competent authorities and other stakeholders [31]. The early studies showed that convalescent plasma infusion to COVID-19 patients is safe and effective.”(1) 

But the latest results were not so positive. 

Af the end we can say, what matters is preparedness, “response strategies implemented by national authorities, adapted human behavior as the key to tackling this pandemic.” 

(1) https://www.ecdc.europa.eu/en/covid-19/latest-evidence/vaccines-and-treatment