The last two years have taught epidemiologist a lot about real time surveillance of transmissible diseases.
One of the lessons learned is that sewage water can tell you a lot about a population.
So in response to the covid-19 pandemic, the U.S. Centers for Disease Control launched the National Wastewater Surveillance System (NWSS) in September 2020.
The NWSS was created to coordinate and track the covid virus in wastewater samples collected across the country.
"This allows wastewater surveillance to serve as an early warning that COVID-19 is spreading in a community. Once health departments are aware, communities can act quickly to prevent the spread of COVID-19," the CDC says.
Wastewater surveillance can serve as an early warning system that can detect small changes in the prevalence of a disease. Epidemiologists from Yale were able to detect poliovirus in sewer water during the polio outbreak in the summer of 1939.
"This virus can be transported, for short distances at least, through the medium of flowing sewage," Yale scientists concluded at the time.
In 2022, while covid has started to take a back seat to other public concerns, wastewater surveillance is now giving the CDC data on another potential outbreak that has resulted in California and New York City both declaring a state of emergency.
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Monkeypox on the Strip
As of Aug. 1, there are 23 probable and confirmed cases of monkeypox in Clark County and the Southern Nevada Health District is looking through the poo to keep a handle on the situation.
“The good thing is that the monkeypox signal is relatively low and it is coming from strategic manholes that service segments of the Las Vegas Strip and from at least 1/15 wastewater treatment plants,” UNLV associate professor Dr. Edwin Oh told CBS8 in Las Vegas.
The UNLV surveillance program covers about 2.4 million people and that coverage should be able to detect if there are increasing incidences of the virus in the population.
The wastewater being studied originates from water coming from casinos and hotels located on the Strip and other locations in the region.
Infected people with monkeypox excrete viral DNA through skin lesions, saliva, feces, and urine.
"The viral levels are currently low from our readings, suggesting that high transmission is not occurring in Las Vegas,” Oh said, according to Casino.org. “Because infected individuals (who may be asymptomatic or symptomatic) will shed the virus, the actual number of infected people may be higher than the reported numbers.”
Monkeypox infection usually comes from skin-to-skin contact with an infected person and can be transmitted through sexual contact as well. The virus is painful but only occasionally fatal.
Infections in Major Cities
Last week, San Francisco became the first major city to declare a public health emergency due to an increasing number of monkeypox cases.
The over the weekend New York City followed suit.
New York Mayor Eric Adams called the five boroughs the "epicenter" of the country's monkeypox outbreak, saying that as many as 150,000 city residents may be at risk of exposure.
New York Gov. Kathy Hochul (D) issued a state disaster emergency that will enable additional health care workers, including EMTs and midwives, to administer the vaccine.
Monkeypox symptoms usually start off with a flu-like illness, followed by the appearance of rashes. Symptoms include: fever, headache, muscle aches, backache, exhaustion, swollen lymph nodes, and chills, according to the SNHD.
The rash looks like pimples or fluid-filled blisters that can occur on the hands, feet, chest, face, genitals, or inside the body, including the mouth, vagina, or anus.
It often takes between seven and 14 days after exposure to develop symptoms. Monkeypox typically lasts for between two and four weeks.
