Nine students at the same Virginia high school have overdosed on suspected fentanyl in less than a month, prompting the state's governor to issue an executive order calling for greater transparency for parents.

All of the overdoses involved opioids suspected to contain fentanyl, and four of them happened on campus at Park View High School in Sterling, about 30 miles northwest of Washington D.C., according to the Loudoun County Sheriff's Office and the office of Virginia Gov. Glenn Youngkin.

No deaths have been reported from the overdoses, the most recent of which happened on Tuesday. The students' ages and conditions haven't been released.

Here's what we know:

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Districts to notify parents of school-connected ODs within 1 day

Youngkin, a Republican, on Tuesday signed Executive Order Twenty-Eight requiring parents be notified of any school-connected overdoses within 24 hours.

The order also requires districts to "work closely with law enforcement to prevent overdoses, and enhance student education about the dangers of abusing drugs."

"While the Loudoun County Public School division reportedly waited more than 20 days to notify parents to the overdose incidents," according to a statement from Youngkin's office. "Failure to promptly notify parents endangers the health and welfare of their children and limits parents’ fundamental right to make decisions concerning the upbringing, education and care of their children.”

In addition to the nine cases at Park View, Youngkin's order referenced 19 juvenile opioid overdoses in Loudoun County so far this year.

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Law enforcement working closely with school security

The sheriff's office reported that four of the nine Park View overdoses happened in the school, with Narcan administered in three of those cases and school personnel administering CPR in two cases.

The other five overdoses, including the one on Halloween, happened at residences, sheriff's spokesperson Michele Bowman told USA TODAY.

The sheriff's office assigned "additional resources" to Park View High School to identify the source and distribution of the opioids, and is working closely with school officials and security personnel, the agency said in a news release.

“I am concerned and saddened by this crisis impacting the Park View community,” the district's Superintendent Aaron Spence said in a statement. “(The district) is taking active steps to support our students, families and staff with fentanyl awareness and education, including training and supplying staff in each of our high schools with naloxone for emergencies."

What is fentanyl?

Fentanyl is a potent synthetic opioid that is easy to disguise, and can be used alone or mixed with other drugs including heroin, meth and cocaine. Two milligrams of the drug − about the size of a grain of salt − can be lethal depending on a person's size and tolerance. 

The drug is commonly found in the form of blue, fake30 mg oxycodone pills, and may be stamped “M30.”

What is Narcan?

Narcan is the brand name for naloxone, a non-narcotic medication that immediately treats symptoms of an opioid overdose.

The life-saving drug works by temporarily blocking receptors in the brain from linking with opioids so a person overdosing can breathe. It can reverse overdoses of opioids, including street drugs such as heroin and fentanyl and prescription versions including oxycodone.

In March, the U.S. Food and Drug Administration approved the first over-the-counter naloxone nasal spray amid the opioid epidemic. According to the Centers for Disease Control, it can also be administered by people with or without medical training to help reduce opioid overdose deaths.

The move came on the heels of more than 73,000 Americans dying from fentanyl overdoses last year.

In May, the FDA also approved the first nalmefene hydrochloride nasal spray to reverse opioid overdose. Nalmefene is an "opioid receptor antagonist" used to treat sudden opioid overdose and is only available by prescription.

"Opioid overdoses have claimed the lives of far too many Virginians," Youngkin said. We must continue to combat opioid abuse and overdoses with action and transparency," he said. "Parents have a right to know what’s going on in their child's lives, especially in schools. School administrators’ first instinct when there is a problem cannot be to delay relevant information on critical children's health and safety matters − it must be passed on to parents immediately."

Natalie Neysa Alund is a senior reporter for USA TODAY. Reach her at [email protected] and follow her on X @nataliealund.