Is This the Beginning of the End of the Covid Disaster or Is It Only the End of the Beginning

DAILY MAIL: The city where new Brazilian strain defeated herd immunity: Manaus is gripped by surging cases and record deaths despite 75% of the population getting infected during first wave

This is seriously bad news. The report from Manaus of a surging rate of Covid reinfection means, first, that the virus is mutating so rapid that immunity, whether acquired through infection or vaccination, is extremely short-lived; and second, that any T-cell response* to infection is failing to provide immunity to reinfection by some new strains of the virus.

It is also the case that the wave of reinfections in Brazil, could be evidence of antibody-dependent enhancement (ADE), meaning that antibodies produced in response to vaccination may facilitate infection by, and enhance the virulence of, novel strains of the virus.

If a pessimistic interpretation of the report from Brazil is correct, the Covid disaster is only now beginning to take shape. What we could then expect is:

Not an end to quarantine for international travelers, but an end to international travel.

Not an end to pub and restaurant closures, but an end to pubs and restaurants.

Not an end to work from home, but an end to most work.

Not an end to home schooling, but an end to schools.

___

* Immunity to viral disease normally depends on both a long-term T-cell response that resists reinfection, and a short-lived antibody response that combats the disease following infection.

The Covid-19 mRNA vaccines induce an antibody response but no T-cell response. Hence, while they prevent manifestation of disease they do not prevent infection or, therefore, the spread of infection.

Thus, it was to be hoped that because it entailed a T-cell response, resistance induced by infection, unlike that induced by vaccination, would be long-lived. The report from Brazil of widespread reinfection among those previously infected means that this hope was ill-founded.

Related:

Oil Plunges Below $60 After Brazil-Variant Virus Headlines