The two unknown tick diseases that are killing many Chinese

by Michael Woodhead
Two virtually unknown tick born rickettsial diseases have become a serious threat to human health in China, health authorities have warned. In just a few years the diseases caused by tick-borne A. phagocytophilum and E. chaffeensis have become common in rural areas and cause disease including multiple organ failure and death, according to Dr Zhang Lijun and colleagues at the Department of Rickettsiology, National Institute for Communicable Disease Control and Prevention, Beijing.
In a new paper they report that the first cases of human granulocytic anaplasmosis (HGA) occurred in Anhui Province in 2006 and then in Shandong. They said human granulocytic anaplasmosis is a serious disease in which about half of patients are hospitalised, 40% of patients have multiple organ dysfunction syndrome, and the fatality rate can be as high as 8%. However, they suspected that in China infections with the two rickettsial diseases were often not recognised, and were misdiagnosed as hemorrhagic fever with renal syndrome (HFRS).
In their own study they analysed 7,322 serum samples from farmers  and found that 10-15% farmers had been exposed and were at substantially increased risk of the diseases. A second analysis of 819 blood samples from urban residents from showed that 4-12% of urban residents had been exposed and were also at high risk of the tick-borne diseases. Worryingly, the infections were carried by a wide range of ticks, not just one species, and the ticks were found on many domestic animals and livestock including dogs, goats, sheep, cattle, horses, rabbits and rodents.
"In China, the free-range feeding of animals is a major part of livestock production, in contrast to livestock production in modern developed countries. Animals roam hills for feeding during daylight and return at sundown. In such a situation, animals can return with many ticks from wild fields. Moreover, most farm families own two to three dogs for guarding their animals and belongings, and these dogs also roam freely in and out of yards. Therefore, it is not surprise that contacting with domestic animals is regarded as a main exposure risk," they noted in Biomed Research International
The researchers concluded that the wide distribution of the tick-borne infections and their serious nature meant that their transmission and risk factors "urgently needed to be further investigated."
[Editor's Note: The risk of tick borne diseases in China is not insignificant: a US student became paralysed after being bitten by a tick during a school trip to China and was awarded $42 million in damages against her school in a US court last year]

China medical news for Sunday 2 February

Cosmetic procedures a high risk for hepatitis C
Chinese people are more likely to contract hepatitis C from a cosmetic and beauty treatments than from medical procedures or blood transfusion, a study from Jilin shows.
Researchers found that hepatitis C rates had increased rapidly in Yanbian, Jilin, more than doubling from  2007 to 2011. Unexpectedly, they found that cosmetic treatments conferred the higest risk - almost five fold higher than control groups. Having someone esle in the family with HCV was also a high risk for infection, presumably through sexual transmission between spouses, the researchers said. Writing in PLOS One, the researchers for the Capital Medical University, Beijing, said cosmetic treatments had become popular in recent years and there was a risk of viral infection with procedures that broke the skin such as shaving and ear piercing.

Atherosclerosis defined in stroke
Intracranial atherosclerosis (ICAS) is the most common vascular lesion in patients with cerebrovascular disease in China, a study  has shown. Researchers at the Tiantan Hospital in Beijing assessed 2864 consecutive patients who experienced an acute cerebral ischemia and found the prevalence of ICAS was 47%. Patients with ICAS had more severe stroke at admission and stayed longer in hospitals compared with those without intracranial stenosis. According to the study in Stroke, after 12 months, recurrent stroke occurred in 3.3% of patients with no stenosis, in 3.8% for those with 50% to 69% stenosis, in 5.2% for those with 70% to 99% stenosis, and in 7.3% for those with total occlusion.

STI risk high for men who visit prostitutes
Men who have unprotected sex with prostitutes are at high risk of HIV and syphilis, Guangxi research has shown. A study of more than 100 men who visited prostitutes found a high rate of unprotected sex (84%). The overall prevalence of HIV, hepatitis C and syphilis was 1.9%, 1.0% and 18.4%, respectively, according to the study published in Sexually Transmitted Infections.

Parasite problems on the Tibetan plateau
Worm parasites are an endemic problem for Tibetans, especially nomadic herders, a study has found.
Echinococcosis affects more than 380,000 people on the Tibet-Qinghai plateua, is spread by dogs and cattle, and is often picked up from drinking groundwater, according to a study by Chinese researchers. Those most at risk include the old and female in particular. Writing in Infectious Diseases of Poverty, the researchers said control of the parasites should focus on deworming both owned and stray dogs and health education activities n Tibetan language.

Scrub typhus - a growing problem for China and it's spreading to Beijing

by Michael Woodhead
A study by Beijing researchers has shown that life threatening scrub typhus remains an important public health problem in China, and action is need to curb its spread into areas such as Beijing.
Scrub typhus is a serious infection for which there still no effective and reliable  vaccine and no point-of-care diagnostics available.
Dr Zhang Wen-Yi and co-workers from the Institute of Disease Control and Prevention, Academy of Military Medical Science, Beijing analysed surveillance data and found that there has been a sharp increase in cases of the disease, with 27,391 confirmed cases of scrub typhus  reported in China during 2006–2012
 Scrub typhus cases were mainly located in areas of high population density in southeastern and southwestern China, "indicating that many millions of people are at risk of infection," they report in PLOS Neglected Tropical Diseases.
Most scrub typhus cases occurred between July and November, which may be associated with increased exposure to infected chigger mites during the harvest season. The disease was common in elderly farmers and in rural children, perhaps due to exposure during outdoor play .
"Importantly, this study identified a primary cluster located in 176 counties of Guangdong Province, Fujian Province, Jiangxi Province, and Guangxi Province, which is considered the main persistent foci of scrub typhus in China. These areas should be targeted by policy-makers and local service providers for the establishment of refined disease control guidelines, including local vector control, health education, and promotion campaigns."
Their study also identified other newly-identified high-risk clusters of scrub typhus, including some cases in the capital Beijing, that resulted from the importation of infection from other provinces in 2007.

Imported schistosomiasis a risk as China develops closer links with Africa

Experts in parasitic disease say imported schistosomiasis is an increasing problem for China as more Chinese travel to Africa
Dr Lu Ping and colleagues from the Key Laboratory of Technology on Parasitic Disease in
Wuxi say that the chronic, debilitating parasitic disease caused by trematode blood flukes is a major public health threat for China. Writing in the Journal of Travel Medicine, they say that at present, only S. japonicum is endemic in China. However, more and more imported cases infected with African schistosomes (including S. mansoni and S. hematobium) are reported owing to the sharp growth in China-aided projects in Africa and labor services exported to Africa. Since 1979, a total of 147 cases infected with S. mansoni and 283 cases infected with S. hematobium have been reported until now, including the two S. hematobium-infected workers returning from Tanzania and Angola They note that there are now over a million Chinese workers now residing in Africa, who have a high risk of exposure to African schistosomiasis, and many infected individuals are asymptomatic and seldom seek care and have a high rate of missed diagnosis and misdiagnosis due to the lack of knowledge on African schistosomiasis;
"Therefore, it is considered that the actual number of the Chinese infected with African schistosomes may be greatly underestimated.
And once the infected cases, as sources of infection of schistosomiasis, are imported to regions where the snail intermediate hosts of African schistosome are present, there is a high likelihood of transmission of African schistosomiasis in China, they say.
A systematic surveillance and evaluation program for schistosome infections in returners from African countries is urgently required under the organization of health sections, entry-exit inspection and quarantine sections, and commerce sections, they suggest.

Schistosomiasis control program proves highly effective at Poyang Lake

Researchers from Shanghai have shown that a Schistosomiasis control program has been highly effective in almost eliminating the infection from the Poyang Lake region of China.
Researchers from the National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai assessed the impact of a comprehensive schistosomiasis control program started in 2003. In 2003, the prevalence of Schistosoma japonicum infection ranged from 6.5% to 11.3% in the program sites. In 2006, the control program reduced schistosomiasis infection to levels of 0.6% to 1.6%. The US$10,000 cost of the program reduced prevalence of schistosomiasis nine-fold. And was deemed to be highly cost-effective.
“This work clearly shows the improvements in both cost and disease prevention effectiveness that a comprehensive control program-approach has on schistosomiasis infection prevalence.”
Full study: International Journal of Environmental Research and Public Health

Schistosomiasis a huge and overlooked problem in 'non endemic' areas of China

Migrants are spreading schistosomiasis to non-endemic areas

by Michael Woodhead
Urgent action is needed to improve control of schistosomiasis which is out of control in areas of China that are supposed to have no endemic disease, experts in parasitology have said.
China has an effective system of screening and treatment that has been set up in endemic areas  for schistosomiasis, which is caused by trematode blood flukes of the genus Schistosoma, says Dr Zhou Xiao-Nong of the National Institute of Parasitic Diseases at the China Centres for Disease Control.
However, a recent case in a non-endemic area showed that even patients with advanced disease are unable to get adequate and timely diagnosis  and treatment in many parts of China, he says. This especially applies to migrant farmers workers who may travel from endemic to non-endemic areas, says Dr Zhou.
He cites the example of a woman from a nonendemic area within the Anhui Province of China who had advanced schistosomiasis. During a period of one and a half months, the patient went through two hospitals, one preventive institute, and two regional schistosomiasis control stations, three of which she had been admitted into for medical treatments. Although the patient was not misdiagnosed from the beginning, she did go through five medical or health service facilities in pursuing medical treatment, covering a distance of nearly 1,000 km. Dr Zhou says diagnosis and treatment of schistosomiasis with praziquantel should be relative straightforward if a system is in place.
"Due to an unprecedented migration rate of populations in China as well as in other developing countries the number of such missed or ignored advanced cases could be huge.  Therefore, an improvement in the current monitoring system and aid-project management (i.e., enrolling vulnerable populations who have migrated from an endemic to nonendemic areas)  is clearly and urgently needed. This seems of great importance when the control and elimination of schistosomiasis has been put on the agenda," he concludes.
Source: PLOS Medicine

In Guangxi, 60% of villagers infected with liver flukes

Liver flukes and minute intestinal flukes are endemic in some parts of Guangxi

by Michael Woodhead
A study of villagers in rural Guangxi province near Nanning has found that around 60% of them are infected with fish-borne trematodiasis, manifesting as liver flukes or intestinal flukes.
The liver flukes caused by Clonorchis sinensis appear to be endemic in the region and can cause chronic diseases and are a neglected public health issue in the area, say parasitologists who carried out a study in six rural villages in southern Guangxi.
Their analysis of faecal samples from more than 700 local residents found an overall egg positive rate of 60% (428/718) for C. sinensis and minute intestinal flukes. In some villages the rates were as high as 70%, and cases of heavy fluke infection were seen in up to 18% of villagers.
The researchers say the rates are higher than previously seen and reflect the endemic nature of the liver flukes in the area. The prevalence of C. sinensis infection was found to be 0.4% in a nationwide survey in China between 1988 and 1992, they note.
The infections come from infected fish int he area say researchers form Korea working in conjunction with scientists from the Guangxi Center for Disease Prevention and Control, Nanning. 
Source: Korean Journal of Parasitology