Johnson & Johnson's vaccine distribution will be cut by nearly 86% next week, according to the Centers for Disease Control and Prevention.

The decrease is due to 15 million doses of the vaccine having to be thrown out in March because a key ingredient didn't meet quality control.

This week, some vaccination sites across the country were shut down after a small number of people had mild adverse reactions.

Johnson & Johnson distributed nearly 5 million vaccine doses across the country, and next week they will only be giving out 785,000.

The news comes as cases of the coronavirus on Long Island are increasing due to the spread of new variants.

Suffolk County Executive Steve Bellone calls the reduction a setback.

"So as we think about vaccine hesitancy, a reduction in J&J can have a real impact on us," says Bellone.

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Nassau County Executive Laura Curran agrees but is confident in the progress of the county's vaccination program.

"We're doing very well. We have a good program. We've had 42% of our residents receive at least one dose - that's 57% of the adult population. So we are really leading the state here."

Most mass vaccination sites across Long Island have been administering the Moderna and Pfizer vaccines, which will remain steady.

Select pharmacies like CVS and Walgreens have been receiving doses of Johnson & Johnson.

Gov. Andrew Cuomo released a statement, saying: "Vaccines are the weapon that will win the war against COVID, and with over 11 million shots in arms - including 1.4 million doses administered in just the last seven days - New York's vast distribution network is firing on all cylinders. As has been the case since the beginning of our vaccination effort, the X-factor is supply, supply, supply, and like every other state, our allocation of Johnson & Johnson doses will be significantly lower next week.

"In Week 18, New York will receive just 34,900 Johnson & Johnson shots - a drop of 88% week-over-week and the first decrease in weeks - while no appointments should have to be cancelled, we will not be able to get as many shots into New Yorkers' arms as we would like. We hope the production issues are resolved as soon as possible, and that production ramps up quickly so we can expand the number of New Yorkers who are vaccinated. In the meantime, we thank the Biden Administration for their herculean efforts to vaccinate all Americans, and look forward to continuing our partnership to stamp out COVID once and for all. As we continue to roll out vaccines, everyone must remember to wear masks, socially distance, wash their hands, and stay New York Tough."