Delta becomes dominant variant in New York, accounting for two-thirds of new cases

The delta variant now accounts for the majority of new COVID-19 cases in the five boroughs, according to data released Thursday by the New York City Department of Health and Mental Hygiene. The derivative germ became the city’s most common variant in less than five months.

Delta accounts for 69% of cases analyzed between June 27 and July 3, the most recent slice of samples analyzed by a city-wide effort including the New York Public Health Laboratory, the Response Laboratory to the pandemic, hospitals and private clinics. This represents an increase from 44% of cases tested the previous week. Delta became New Jersey’s predominant variety earlier this week and won the national title shortly after Independence Day.

The delta variant, which was first spotted in city surveillance in February, is more contagious and more resistant to our immune defenses compared to the original virus. The Pfizer, Moderna, and Johnson & Johnson vaccines can still neutralize the delta variant, although it appears to be more likely to cause breakthrough infections. (Thursday a number of New York Yankees players tested positive for COVID-19, would have including at least three vaccinated players.)

Delta rose to prominence in New York as other variants fell, the latter likely being tamed by vaccines.

Read more: Why the Delta variant matters whether you’re vaccinated or unvaccinated

Based on growing evidence, a full vaccination will protect against serious illness and hospitalization. Los Angeles officials on Thursday announced the county would be reintroducing its indoor mask mandate for everyone, regardless of their immunization status.

“The rise of the delta variant in New York City means this may be the most dangerous time to go unvaccinated,” a spokesperson for the city’s health department told WNYC / Gothamist. “All New Yorkers should be vaccinated against COVID-19 to protect themselves, their families and our city. “

Read more: How parents can prepare for the Delta variant since most children are not vaccinated

Only a small fraction of confirmed COVID cases are tested for viral variants, but the city’s health department says the results generally match city-wide trends. Since some samples are tested by hospitals and the medical examiner, the results may bias in favor of more serious cases. Any recent data reported by the health service is also provisional and may change over time as pending cases are assessed.

The findings come as COVID positivity rates rise in some neighborhoods, namely East Harlem and parts of Staten Island. Citywide, the seven-day case average fell from 133 on June 20 to 438 on July 12. Hospitalizations and deaths remain at their lowest levels, but severe illness is traditionally a few weeks behind the initial infection.