#15,411
With the caveat that this is an anecdotal report, and details are scant, we have a report - issued by the Jingzhou City government - indicating that a 68 year-old woman who was infected with COVID-19 more than six months ago, has tested positive again for the virus.
At this point we don't know if this is a reactivation of a dormant virus, or a re-infection, although Chinese officials are quick to call it a `rejuvenation' of the virus (not a new case).
This isn't the first time we've seen patients test positive again after supposedly being `cured' (see Feb 27th's Osaka Japan: `Recovered' Patient Tests Positive For COVID-19), but most of the time these cases tested positive again within a few weeks following `recovery', suggesting they were more likely the result of testing failures or relapses than re-infection.
- We've seen `relapses' before with another severe coronavirus (see Korean Govt. Statement On MERS Patient `Relapse’ and Isolation). In this case, the patient had significant comorbidities, which may have led to a longer-than-normal carriage of the virus.
- False negative COVD-19 test results have been common enough (see Problematic Lab Testing For The Novel Coronavirus) that last spring Hubei Province required self-isolation for an additional 14 days for cases following release from the hospital.
Xinhuanet is reporting:
2020-08-12 16 :10: 24Source : CCTV News Client
According to the report of the New Crown Pneumonia Epidemic Prevention and Control Headquarters in Jingzhou City, Hubei Province on the 12th, on August 9, a 68-year-old female retired worker from Lianhe Street, Jingzhou Development Zone, was hospitalized due to illness. The new crown virus nucleic acid test was positive. The woman was The patient with new coronary pneumonia diagnosed on February 8 was cured again after a few months. It is not a new case.
At present, the patient is treated in isolation again, and all contacts have been tested negative for nucleic acid, and his residence and activity area have been thoroughly disinfected, and the risk is completely controlled. There is no evidence that there is a risk of transmission of Fuyang cases. The citizens are requested not to panic, believe or spread rumors. Remind the general public that personal protection should also be emphasized under normal circumstances.
If, as local officials are insisting, this is a case of reactivation after six months of dormant carriage of the virus, then COVID-19 could have some interesting surprises ahead.
The `no evidence of a risk of transmission' from a reactivated case sounds more like hope than reason, but even if true, this raises new questions about the long-term individual health impacts of infection.
The `other' possibility is that this woman was re-exposed to the virus, and was reinfected.
Admittedly, the case for this being a new infection is flimsy at best. Not only would this woman have to have been re-exposed during a time when the Chinese are reporting only a handful of new cases each day, she'd have to have lost any acquired immunity after just 6 months.
Waning immunity after 6 months, however, is not much of a stretch given some of the serological studies we've seen.
Less than a month ago, Nature published the following news article :
(Excerpt)
16 July — Antiviral antibodies peter out within weeks after infection
Key antibodies that neutralize the effects of the new coronavirus fall to low levels within months of SARS-CoV-2 infection, according to the most comprehensive study yet.
(SNIP)
However, in most people, antibody levels began to fall about a month after symptoms appeared, sometimes to nearly undetectable levels — raising questions about the durability of vaccines designed to promote the production of neutralizing antibodies.
(Continue . . . )
So the timing, at least, would seem plausible for a re-infection. As to the likelihood of her being re-exposed to the virus, that requires data that only China knows with any certainty.
A genomic sequence analysis of this patient's virus - comparing it to the virus that was circulating in China in late January - could provide better insight into what is happening here. Whether that will be done, and shared by Chinese officials, is anyone's guess.
But if, over the next few months, we start seeing a significant number of similar reports - both from China and around the world - then we'll know that COVID-19 has yet another curve ball to throw at us.
Stay tuned.