A seventh patient has died after suffering from severe lung disease potentially linked to vaping.

The second such case is from California and was confirmed Monday by the Tulare County Health and Human Services Agency. Other cases have come from Indiana, Illinois, Kansas, Minnesota, and Oregon, NBC News reports.

“With sadness, we report that there has been a death of a Tulare County resident suspected to be related to severe pulmonary injury associated with vaping,” said Dr. Karen Haught, public health officer for Tulare County, California. “The Tulare County Public Health Branch would like to warn all residents that any use of e-cigarettes poses a possible risk to the health of the lungs and can potentially cause severe lung injury that may even lead to death. Long-term effects of vaping on health are unknown. Anyone considering vaping should be aware of the serious potential risk associated with vaping.”

Little is known about the specifics of this most recent death. Past cases, like the sixth death, have shown that older patients and those with preexisting medical conditions might be at a much higher risk of developing a severe illness due to vaping.

The Center for Disease Control [CDC] has confirmed around 380 cases of severe lung disease that have either been confirmed to be or are highly likely to have been caused by vaping. Health departments in 43 states have reported over 500 potential cases of vaping-related conditions.

“CDC has made it a priority to find out what is causing this outbreak of e-cigarette or vaping-related injuries and deaths,” said Dr. Robert Redfield, the CDC's director.

The center has yet to pinpoint any specific product or products that may be to blame but nicotine and cannabis liquids have been under heavy scrutiny. The public has been advised to avoid e-cigarettes in general, but especially those offered by street vendors.