The COVID-19 pandemic has highlighted the need for rapid and accurate diagnosis of deadly diseases. Sexually transmitted infections (STIs) can also be devastating, and timely detection can prevent the escalation of damage to health. One such STI is gonorrhea—a bacterial infection. Now, researchers have developed an inexpensive portable device and a complimenting smartphone app that can diagnose infection in under 15 minutes.
A team led by scientists from Johns Hopkins University has created a diagnostic device called PROMPT (portable, rapid, on-cartridge, magnetofluidic purification and testing platform). The invention not only diagnoses infection quickly but can also determine whether the particular strain of the gonorrhea bacteria can be treated using frontline antibiotics.
"Our portable, inexpensive testing platform has the potential to change the game when it comes to diagnosing and enabling rapid treatment of sexually transmitted infections. It ensures that patients are diagnosed on the spot, and treatment can begin immediately, improving clinical outcomes. This will be especially valuable in low-resource settings, where well-equipped laboratories are not always available to every patient," said team leader Prof. Tza-Huei Wang, in a statement.
A Lethal Bargain
Gonorrhea is a common and potentially deadly sexually transmitted infection that affects both men and women. It is caused by the bacteria Neisseria gonorrhoeae and spreads through unprotected oral, vaginal, anal sex. Pregnant mothers can transmit the infection to their new babies whose eyes are affected. According to the WHO, in 2016 alone, 87 million people across the world had contracted gonorrhea.
The infection can affect not only the genitals but also other organs such as the mouth, rectum, and throat. In females, the cervix can also be impacted; leading to infertility in some cases. Symptoms of the infection usually manifest within 2 to 14 days following exposure. However, several infected individuals may not develop discernible symptoms and often serve as asymptomatic carriers.
Symptoms in women include vaginal discharge, painful intercourse, and abdominal pain, among others. In men, discharge from the penis, burning sensation during urination, and swelling of the testicles are some of the symptoms. Treatment of gonorrhea involves the oral or injected (or both) administration of a single or a combination of antibiotics. However, like numerous other bacteria, strains of antibiotic-resistant N.gonorrhoeae have emerged; rendering existing drugs ineffective.
Ease of Mobility
PROMPT is powered by a simple five-volt battery and includes thermoplastic cartridges costing around $2. The working of the test is rather simple. Body fluid of a patient collected using a swab is mixed with a solution of magnetic particles in a tube. Next, a drop of the blended solution is placed inside a cartridge which is attached to the device.
Now, the device transfers these magnetized particles to reagents within the cartridge, which is run through 40 cycles of polymerase chain reaction (PCR) testing. Finally, the results are displayed on the cellphone screen through the app. PCR testing helps in the amplification of DNA acquired through tiny samples. Importantly, PCR currently forms the gold standard for COVID-19 testing.
High Accuracy and Speed
When PROMPT underwent testing at sexual health clinics in Baltimore, USA, and Kampala, Uganda, it identified the most commonly prevalent strain of N.gonorrhoeae around 97 percent of the time. Also, it showed 100 percent accuracy when it came to ascertaining whether the tested strain of the bacteria would respond to treatment using ciprofloxacin, an antibiotic that is used to treat infections that exhibit resistance to other antibiotics.
The portability and speed of the invention is an improvement of conventional testing methods employed in hospitals and laboratories which take up to a week to provide results. The reduction of this waiting period is crucial as it can prevent the unknowing spread of infection to more people by the infected individual.
"Our test maintains the same sensitivity and specificity currently used in hospital and clinic labs but reduces the cost and time involved. We want these diagnostics to be available to all people who need it, when they need it," expressed Alex Trick, co-author of the study. A university spinoff is being formed by the team in order to deal with regulatory approval, manufacturing, and distribution.