Henan Province has been in the malaria elimination stage, with all reports of the disease being imported since 2012 and over 90% coming from Africa. Surveillance and population studies are essential for the early detection and subsequent prevention of the spread of drug resistance. The K13-propeller gene was recently identified as a proposed molecular marker of artemisinin (ART) resistance. In this study, we detected mutations of the K13-propeller gene in samples taken from imported malaria cases in Henan Province from 2012 to 2015. There were 483 samples that were obtained from Plasmodium falciparum–infected malaria migrant workers who returned to Henan Province from Africa between 2012 and 2015. The single nucleotide polymorphisms in the K13-propeller gene were assessed by nested PCR with DNA sequencing. Frequency and geographic difference of K13-propeller gene mutant types were analyzed. Of 483 patients, 476 were cured and 7 died. There were no K13-propeller mutations in the blood samples from the 7 patients who died, but there were 23 different genotypes of the K13-propeller that were observed in 24 (4.97%) of the samples. C580Y, which was the predominant one in the resistance of ART, was not detected in the samples, but R539T and P574L which have also been associated with ART resistance, were observed in two samples from Angola and Equatorial Guinea. No mutations were detected in 11 samples from North Africa. The frequency of the K13-propeller was 6.50% (8/123) in Central Africa, followed by East Africa (1/19, 5.26%), West Africa (9/198, 4.55%) and South Africa (6/132, 4.55%). There was no significant difference among these four areas (P = 0.795). R539T and P574L were found in migrant workers who traveled from Africa to Henan Province, although the frequency of the K13-propeller mutants was low. These data may enrich the molecular surveillance of antimalarial resistance and will be helpful for developing and updating the antimalarial policy in Henan Province.

Anti-malarial drug resistance is a primary public health problem. Haplotypes of pfcrt gene have been implicated to be molecular markers of chloroquine (CQ) resistance. This study aims to explore the prevalence of polymorphisms in pfcrt in Plasmodium falciparum-infected patients imported from Africa in Henan province. Blood samples were collected from 502 patients who were infected with P. falciparum returning from Africa in Henan province during 2012–2015. The single nucleotide polymorphisms in pfcrt (codons 72–76) were assessed by nested PCR with DNA sequencing and restriction digestion, the haplotype prevalences were also determined. Four haplotypes coding 72–76 of pfcrt were found including CVMNK (wild type), CVIET (mutation type), CVIEK (mutation type), and CV M/I N/E/D/K K/T (mixed type), with 61.95 % (311/502), 33.07 % (166/502), 0.20 % (1/502), and 4.78 % (24/502) prevalence, respectively. Except mixed type, CVIET and CVIEK were the largest proportion of the mutant type in West Africa, accounting for 44.83 % (91/203), followed by East Africa (8/21, 38.10 %), North Africa (4/11, 36.36 %), Central Africa (36/135, 26.67 %), and South Africa (28/132, 21.21 %). There was significant difference among the groups (χ2 = 23.78, P < 0.05). Mixed type was the largest proportion in North Africa (9.09 %), followed by Central Africa (6.67 %), East Africa (4.76 %), South Africa (4.55 %), and West Africa (3.45 %). There was no significant difference among the groups (χ2 = 2.31, P > 0.05). The position 72 and 73 of pfcrt showed predominance for the wild type with rates of 100 % (502/502). This study identified four haplotypes of pfcrt in P. falciparum-infected patients imported from Africa in Henan province. The prevalence of mutations in the pfcrt was dropped comparing with other people’s researches. It establishes fundamental data for detection of P. falciparum CQR with molecular markers for the imported P. falciparum in China, and it also provides complementary information of CQR for the malaria endemic countries and assesses the evolution of anti-malarial drug resistance.

Visceral leishmaniasis (VL) was widely prevalent in Henan Province in the 1950s. Through active efforts by the government, there were no local cases reported from 1984 to 2015. In 2016, local VL cases reoccurred, and there was an increasing trend of VL cases in Henan Province. To provide a scientific control of VL, an investigation was conducted in Henan Province from 2016 to 2021. The data from VL cases were obtained from the Disease Surveillance Reporting System of the Chinese Center for Disease Control and Prevention. The rK39 immunochromatographic test (ICT) and PCR assay were performed among high-risk residents and all dogs in the patients’ village. ITS1 was amplified, sequenced, and subjected to phylogenetic analyses. A total of 47 VL cases were reported in Henan Province during 2016–2021. Of the cases, 35 were local, and they were distributed in Zhengzhou, Luoyang, and Anyang. The annual average incidence was 0.008/100,000, showing an upward trend year by year (χ² = 3.987, p = 0.046). Their ages ranged from 7 months to 71 years, with 44.68% (21/47) in the age group of 0–3 years and 46.81% (22/47) in the age group ≥15 years. The cases occurred throughout the year. The high-risk populations were infants and young children (age ≤3), accounting for 51.06% (24/47), followed by farmers at 36.17% (17/47). The ratio of males to females was 2.13:1. The positive rates of rK39 ICT and PCR were 0.35% (4/1130) and 0.21% (1/468) in the residents. The positive rates of rK39 ICT and PCR were 18.79% (440/2342) and 14.92% (139/929) in the dogs. The ITS1 amplification products in the patients and positive dogs were sequenced. The homology between the target sequence and Leishmania infantum was more than 98%. The phylogenetic analysis indicated that the patients and the positive dogs were infected by the same type of Leishmania, which was consistent with the strains in the hilly endemic areas in China. This paper showed that patients and domestic dogs were infected by the same type of L. infantum and that the positive rate in dogs was relatively high in Henan Province. Because the measures of patient treatment and culling of infected dogs were not effective in reducing VL incidence in Henan Province, it is urgent to develop new approaches for the control of VL, such as wearing insecticide-impregnated collars on dogs, treating the positive dogs, spraying insecticide for sandflies control, and improving residents’ self-protection awareness to prevent the further spread of VL in Henan Province.

Vivax malaria was historically epidemic in Henan Province of China and Anopheles sinensis was the main vectors and poor farming communities bare the greatest burden of disease. Knockdown resistance in An. sinensis is one of the mechanisms of resistance against pyrethroids. In the present study, the frequency of mutations from An. sinensis was examined in Henan province, China. Anopheles was collected from Kaifeng, Tongbai, Tanghe, Pingqiao, Shihe, and Yongcheng counties of Henan province in 2013. Molecular identification of Anopheles species was conducted by polymerase chain reaction (PCR) amplifying the internal transcribed spacer 2 (ITS2). Part of the IIS6 domain of the para-type sodium channel protein gene was polymerase chain reaction-amplified and directly sequenced. Frequency and geographic difference of kdr gene mutant types were analysed. 208 Anopheles were received molecular identification, of which 169 (81.25%) were An. sinensis, 25 (12.02%) were Anopheles yatsushiroensis, and 12 (5.77%) were Anopheles lesteri. A 325 bp fragment of the para-type sodium channel gene including position 1014 was successfully sequenced from 139 Anopheles, of which 125 (89.93%) were An. sinensis, 12 (8.63%) were An. yatsushiroensis, 2 (1.44%) were An. lesteri. The molecular analyses revealed that mutations existed at codon 1014 in An. sinensis but not in An. yatsushiroensis and An. lesteri. Frequency of kdr mutation was 73.60% (92/125) from population of An. sinensis in Henan province, of which L1014F (TTT + TTC) allele frequencies accounted for 46.40% (58/125), and was higher than that of L1014C(TGT) which accounted for 27.20% (34/125) ( χ2 = 55.423, P < 0.001). The frequency of kdr mutation in Kaifeng county was 100% (49/49), and was higher than that of 37.93% (11/29) in Tongbai, 54.55% (6/11) in Pingqiao, 50.00% (3/3) in Shihe, and 62.50% (10/16) in Yongcheng county, respectively (χ2 = 39.538, P < 0.001; χ2 = 24.298, P < 0.001; χ2 = 25.913, P < 0.001; χ2 = 20.244, P < 0.001). While 92.86% (13/14) frequency of kdr mutation was found in Tanghe county, which was higher than that in Tongbai county (χ2 = 11.550, P = 0.0018). A high frequency of kdr gene mutations from population of An. sinensis in Henan province was found.

In recent years, there has been a substantial increase of imported Plasmodium vivax incidence in Henan Province. As China is in a pre-elimination phase, the surveillance of imported malaria is essential, but there is no good way to distinguish imported cases from indigenous cases. This paper reports a case of a 39-year-old man who acquired P. vivax while staying in Indonesia for one month in 2013, and relapsed in Henan, China in 2014. This was diagnosed as vivax malaria based on rapid diagnostic test, Giemsa-stained peripheral blood smear and Plasmodium species-specific nested PCR. The genetic sequence for the circumsporozoite protein genes was analysed and the genetic variations were compared with a previously constructed database of Chinese isolates. The results from the circumsporozoite protein (CSP) gene sequence analysis centered on the repeat patterns showed that the imported cases had completely different sequences from any subtypes from Chinese isolates, but well matched with the countries travelled by the patient. The imported vivax cases were able to clearly distinguish from the indigenous vivax cases by detecting the CSP gene and were able to confim its origin by genotyping.

The spleen plays a pivotal role in the rapid clearance of parasitized red blood cells in patients with falciparum malaria after artemisinin treatment. Prolonged parasite clearance can be found in patients who have had a splenectomy, or those with hemoglobin abnormalities and/or reduced immunity, which are all distinguishable from artemisinin resistance. This paper reports on a case of prolonged parasite clearance in a Chinese splenectomized patient with falciparum malaria imported from Nigeria. A 35-year-old Chinese male suffered 2 days of febrile illness after returning to Zhumadian city of Henan province from Nigeria on October 1, 2014. The main symptoms were febrile, including the highest axillary temperature of 40 °C, headache, and chills. A peripheral blood smear showed parasitemia (53 913 asexual parasites/μl) of Plasmodium falciparum. The patient had not used any chemoprophylaxis against malaria in Nigeria when he worked there as a construction worker between 2009 and 2014. The patient had three episodes of malaria in Nigeria and had a splenectomy due to a traffic accident 8 years ago from the time he was admitted to hospital. The patient was orally administrated a total of 320 mg/2.56 g dihydroartemisinin-piperaquine for 2 days and intravenously administrated a total of 3 000 mg artesunate for 18 days. The axillary temperature of the patient ranged between 37.0 and 37.7 °C from Day 0 to Day 3, and blood microscopy revealed falciparum malaria parasitemia (26 674 asexual parasites/μl) on Day 3. The patient was afebrile on Day 4, falciparum malaria parasitemia was continuously present and then gradually decreased on the next days, and was negative on Day 21. The patient was cured and left hospital on Day 24 after no plasmodium falciparum was found in the blood on Day 21 to Day 23. No mutation was found in the K13 propeller gene when compared with the PF3D7_1343700 K13 propeller gene reference sequence. This is the first reported case in China of prolonged parasite clearance in a splenectomized patient with imported falciparum malaria. Artemisinin resistance should be distinguished when prolonged parasite clearance is found in a malaria patient who has had splenectomy.