Dödligt virus från Kina orsakar panik (SARS-CoV-2, COVID-19)

Minst 20 personer i Sverige har smittats av den indiska coronavarianten. I början av maj fanns 20 kända fall, uppger Folkhälsomyndigheten (FHM) för Ekot i Sveriges Radio.

I 15 fall finns en koppling till resor från Indien, men hur övriga blivit smittade är ännu oklart. Fallen utreds fortfarande.

Den brittiska regeringens vetenskapsråd SAGE uppgav förra veckan att det är en "realistisk möjlighet" att varianten är 50 procent mer smittsam än den brittiska varianten som tidigare tagit över både i Storbritannien och Sverige.

I Storbritannien har fallen mer än fördubblats två veckor i rad, enligt The Telegraph.

Joakim Dillner, professor i infektionsepidemiologi vid Karolinska institutet, är orolig över spridningen.

- Jag tycker att det är ganska tydligt att den är värre än den brittiska varianten så att den med största sannolikhet kommer att ta över om det inte händer någonting väsentligt angående bättre smittskydd eller bättre immunitetsläge, säger han till Ekot.

Det är oklart om den indiska varianten ger en annorlunda sjukdomsbild än andra varianter. Preliminära testresultat tyder på att de vacciner som används i Sverige fungerar mot varianten, men kanske inte lika bra som mot de varianter som dominerat förut.

inte lika bra som mot de varianter som dominerat förut.

The genomics work was backed up days later by a preprint2 from a team in Germany, which shows that B.1.617 is moderately better than an earlier variant at entering human intestine and lung cells in the lab.

Small studies in animals suggest that the variant could cause more severe disease. In a 5 May preprint3, a team led by virologist Pragya Yadav at the NIV found that hamsters infected with B.1.617 had more inflammation in their lungs than did animals infected with other variants.

Gupta’s team discovered that neutralizing antibodies generated by the vaccinated individuals were about 80% less potent against some of the mutations in B.1.617, although this would not render vaccination ineffective, he says. The researchers also found that some health-care workers in Delhi who had been vaccinated with Covishield, an Indian version of the Oxford–AstraZeneca vaccine, had become reinfected, with most cases tied to B.1.617.

Similarly, the German team tested serum from 15 people who had previously been infected with SARS-CoV-2, and found that their antibodies neutralized B.1.617 about 50% less effectively than previously circulating strains. When they tested serum from participants who’d had two shots of the Pfizer vaccine, they found that the antibodies were about 67% less potent against B.1.617.

Scientists also warn that experiments in serum are not always a good guide to whether a variant can evade immunity from a vaccine in the real world. Vaccines can cause the production of vast quantities of antibodies, so a dip in potency might not be significant. Furthermore, other parts of the immune system, such as T cells, might not be affected.

For example, the B.1.351 variant has been linked to much steeper drops in the potency of neutralizing antibodies, but studies in humans suggest that many vaccines remain highly effective against that variant, particularly at preventing severe disease.

For these reasons, the vaccines are likely to remain effective against B.1.617 and to limit severe disease. “The vaccine is still working,” says Yadav. “If you get vaccinated, you “will be protected, and the severity will be less”.