Illinois public health officials are following the lead of federal authorities by suspending use of the Johnson & Johnson vaccine for COVID-19 while a potentially deadly side-effect is investigated.

The state Public Health Department reported Monday it has notified providers throughout the state to temporarily stop use of the vaccine upon the recommendation of the U.S. Centers for Disease Control and Prevention and the Food and Drug Administration.

U.S. officials reported six cases of a severe blood clot in people who have received th

e J&J vaccine. One death has been reported.

The state has a relatively small number of Johnson & Johnson doses on hand and fewer expected in next week’s delivery. Chicago, with its separate delivery system, postponed until at least next week 13,000 shots of the one-dose J&J vaccine scheduled for this week. At Chicago State University’s vaccination site, shots of the two-dose Pfizer vaccine would be substituted for planned J&J doses, officials said.

Gov. J.B. Pritzker, who suffered no side effects after receiving the J&J vaccine March 24 at the Illinois State Fairgrounds mass vaccination site, said in a tweet Tuesday that the state would send 50,000 doses of vaccines manufactured by Pfizer and Moderna to Chicago to help supply during the next week. He promised another 50,000 in several weeks when it’s time for recipients to get the second of those two-shot vaccines.

More than 47,000 Chicago residents have received the Johnson & Johnson vaccine.

The pause comes at a critical time in the nation’s campaign against coronavirus illness. Several states, particularly in the upper Midwest, have experienced yet another surge in the number of confirmed and probable cases of the potentially deadly, flu-like illness.

Illinois has also experienced another uptick. Tuesday’s number of newly reported infections was 3,193, with 17 additional deaths. Overall, COVID-19 has claimed 21,540 lives in Illinois among 1.29 million cases. But in the past week, an average 133,000 doses of vaccine have been administered daily for a total of 7.34 million shots. That number doesn’t represent fully vaccinated residents.

The state health department said J&J vaccine recipients who suffer headache, abdominal or leg pain, or shortness of breath within three weeks of receiving the shot should contact a health care provider.