HARRIS COUNTY, Texas — *EDITOR'S NOTE: The video above is from September when HCPH confirmed three cases of vaping-related lung illnesses.*

The number of vaping-related lung illnesses in Harris County has increased to six, according to the Harris County Public Health Department.

This is three more than what we last reported in September.

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Most of the people who have fallen ill reside in the northwest Harris County area, HCPH confirmed.

This number does not include Houston-area residents who have experienced vaping-related lung illnesses.

Vaping-related illnesses in the U.S. are still rising, though at a slightly slower pace. As of Oct. 17, there have been nearly 1,500 cases nationwide and at least 33 deaths in the mysterious outbreak, according to health officials.

The outbreak appears to have started in March. Symptoms of the illness include severe shortness of breath, fatigue and chest pain.

Most who got sick said they vaped products containing THC, the marijuana ingredient that causes a high. Overall, about 1 in 10 said they vaped only nicotine.

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In early October, Supermarket chain Kroger and drugstore chain Walgreens announced they would discontinue sales of e-cigarettes at their stores nationwide, citing an uncertain regulatory environment.

In September, Walmart announced that it would stop selling e-cigarettes at its stores nationwide.

The Centers for Disease Control and Prevention has been updating the case counts each week.

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