Medical staff treats a patient with Streptococcus suis infection in the National Hospital for Tropical Diseases. VNA/VNS Photo

HÀ NỘI – Two male patients infected with Streptococcus suis, a pig pathogen, have been recently hospitalised and treated in the General Infectious Diseases Department of the National Hospital for Tropical Diseases in Hà Nội.

The two men had signs of meningitis, sepsis and conductive hearing loss – one of the most severe and common complications, and typically irreversible.

Patient N.V.P., 60, a resident of Bắc Ninh Province, had a history of regularly eating fermented pork made from raw meat and tiết canh (raw pig blood pudding). His family also raises pigs.

Around ten days before hospitalisation, he had a high fever ranging from 39 to 40 degrees Celsius as well as intense headache, nausea and vomiting.

He initially self-treated at home with IV fluids. However, his symptoms only temporarily subsided and as the fever and headache persisted, he visited a healthcare facility and was later transferred to the National Hospital for Tropical Diseases, where he was diagnosed with meningitis and sepsis due to a Streptococcus suis infection.

According to Dr Trần Văn Long from the General Infectious Diseases Department, upon admission, the patient was in an agitated and distressed state, with high intermittent fever, nausea, vomiting and neck stiffness – classic signs of meningitis.

By the second day of treatment, the patient had already lost hearing and showed flushed skin and mucous membranes.

Cerebrospinal fluid (CSF) culture results confirmed Streptococcus suis infection. Additionally, the patient had herpes lesions around the lips, likely due to immune suppression from severe infection.

After 12 days of intensive treatment, the patient’s condition improved significantly. His fever subsided, his CSF became clear again and infection markers stabilised.

Meanwhile another patient, 54-year-old L.V.N. from Lào Cai Province, reported consuming pig intestines and tiết canh one week before the onset of symptoms.

A week later, he developed fever, chills and a headache, and was treated at a local hospital with a diagnosis of sepsis caused by Streptococcus suis.

However, the condition did not improve, and the patient continued with a high fever, headaches, nausea, vomiting, neck stiffness, tinnitus and pneumonia, prompting his transfer to the National Hospital for Tropical Diseases.

Dr Lê Văn Thiệu said lab tests revealed his white blood cell count was twice the normal limit, with a CRP (infection marker) ten times higher than normal. The patient's CSF cell count had reached 1,370 cells per cubic millimetre, his protein levels were six times higher than normal and glucose dropped to 0.54mmol per litre, near the hypoglycaemic threshold.

Neutrophils made up 93 per cent of his white blood cells and staining showed Gram-positive cocci in his CSF, leading to a diagnosis of sepsis and meningitis caused by Streptococcus suis with auditory nerve damage resulting in disrupted or total loss of sound conduction.

“Meningitis and sepsis are two classic clinical manifestations of Streptococcus suis infection in humans. Among its complications, hearing loss is the most common and irreversible,” Dr Thiệu said.

Warning of septic shock and death

Dr Thiệu warned that Streptococcus suis infection in humans can progress rapidly. Mild cases may involve sepsis or pneumonia, but severe cases can lead to meningitis and hearing loss, while extremely severe cases may cause septic shock, multi-organ failure and death without prompt diagnosis and treatment.

As there is currently no vaccine, prevention remains the most important measure.

People must avoid eating tiết canh, under-fermented pork dishes, undercooked pork or unsanitary processed meat products.

In addition, individuals should avoid slaughtering or processing sick pigs or animals suspected to be sick without proper protective equipment.

If symptoms such as high fever, headache, tinnitus or nausea appear, people should immediately visit a healthcare facility for timely examination and treatment to avoid dangerous complications.

“Although the National Hospital for Tropical Diseases has repeatedly issued warnings about this illness, unsafe eating habits remain widespread. This increases the risk of Streptococcus suis infections, endangering public health and lives,” the doctor said.

“People must therefore change their eating and hygiene habits, not only for their own protection but also to safeguard community health,” he added.

Sharp increase in cases

Recently, the number of patients infected with Streptococcus suis across the country has been increasing at an alarming rate.

Although it is not a new infectious disease, its frequency is rising sharply, especially this summer.

According to the infectious disease monitoring system, as of early this year, more than 40 cases of Streptococcus suis infection have been reported nationwide.

Since the beginning of the year, five cases of Streptococcus suis infection have been recorded in Hà Nội, up from the same period in 2024.

In the first two weeks of July, Hà Nội’s Bạch Mai Hospital saw three suspected cases of Streptococcus suis infection.

These cases were linked to eating tiết canh in Quỳnh An Commune, Hưng Yên Province. The individuals had epidemiological links to two others who ate together and later died, initially presenting symptoms such as fever and diarrhoea.

Since the beginning of the year, 38 cases have been reported in Huế, including two fatalities, according to the Huế Centre for Disease Control.

Loopholes in management

Currently, the veterinary and quarantine system still has many loopholes, increasing the risk of disease transmission from pigs to humans.

In many localities, pigs are slaughtered spontaneously, without veterinary inspection or compliance with sanitary conditions. Those who slaughter animals manually often do not use protective gear, making it easy for bacteria to enter through open wounds.

According to the Department of Livestock Production and Animal Health, by 2024, Việt Nam had about 28,000 livestock and poultry slaughtering establishments, of which only just over 800 are centralised slaughterhouses under veterinary control, accounting for less than 3 per cent. Over 90 per cent are small-scale, spontaneous facilities that are not strictly monitored for veterinary and environmental sanitation.

This means that tens of thousands of pigs are slaughtered each day in substandard conditions, increasing the risk of transmission of bacteria like Streptococcus suis.

In HCM City, the largest pork-consuming locality, between 9,000 and 10,000 pigs are slaughtered daily – but only around 20-30 per cent are slaughtered in monitored facilities. The rest come from unlicensed slaughterhouses in Long An Province, many of which do not have quarantine seals or veterinary oversight.

Even as Huế has been put on high alert against Streptococcus suis, on July 9, local authorities discovered a slaughterhouse operating outside of regulated hours. Four pigs suspected of being sick were detected and had to be culled. VNS