Metapneumovirus na mutum

Human metapneumovirus (***'hMPV***' ko hMPV) kwayar cuta, ma'ana guda ɗaya ta RNA ta dangin *Pneumoviridae* kuma tana da alaƙa da ƙungiyar C ta tsuntsaye (AMPV).  An ware shi a karo na farko a cikin 2001 a cikin Netherlands ta amfani da dabarar RAP-PCR (RNA da aka ƙaddamar da PCR) don gano ƙwayoyin cuta da ba a sani ba da ke girma a cikin ƙwayoyin halitta. Ya zuwa shekara ta 2016, ita ce sanarwa ta biyu mafi yawanci - bayan kwayar cutar syncytial (RSV) - na cututtukan numfashi mai tsanani a cikin yara masu lafiya a ƙarƙashin shekaru 5 a cikin babban asibitin marasa lafiya na Amurka.

Mafi girman shekarun asibiti ga jarirai tare da HMPV yana tsakanin watanni 6 zuwa 12, dan kadan ya fi girma fiye da mafi girma na RSV, wanda ke kusa da watanni 2 zuwa 3. Abubuwan asibiti da tsananin HMPV suna kama da na RSV. HMPV kuma muhimmiyar sanadin cutar ce a cikin tsofaffi da jarirai.

## Tarihin lissafi

## Bincike da suna
An fara gano kwayar cutar metapneumovirus (HMPV) a cikin 2001 a cikin Netherlands ta hanyar Bernadette G. van den Hoogen da abokan aikinta. An fara gano HMPV a cikin asirin numfashi na yara 28 a cikin Netherlands kuma da farko sun fito ne daga wasu ƙwayoyin cuta na numfashi na yau da kullun saboda hanyoyin gwajin van den Hoogen da abokan aikinta sun yi ƙoƙari su yi amfani da - gwajin rigakafin ta amfani da takamaiman ƙwayoyin rigakafin ƙwayoyin ƙwayoyin halitta da hanyoyin PCR ta amfani da ƙwayoyin cutar ƙwayoyin halittar ƙwayoyin jini - sun sami damar gwada kawai don ƙwayoyin cututtukanƙarar ƙwayoyin da aka sani kuma, sabili da haka, ba su iya gano sabon kwayar cuta ba.

Lokacin da masu bincike suka fara amfani da dabarun ilmin halitta, ana iya gano halaye na kwayoyin halitta da ɓangarorin jerin kwayoyin halitta na kwayar cutar. Wadannan dabarun sun hada da dabarar PCR da aka tsara ba zato ba tsammani, wanda ya sami iyakantaccen jerin bayanai da ake buƙata don bayyana kyakkyawar dangantaka tsakanin wannan sabon kwayar cutar da cutar huhu ta tsuntsaye. Sabon kwayar cutar, metapneumovirus na mutum, an sanya masa suna ne saboda dangantakarsa ta kusa da AMPV, yana nuna asalinsa a matsayin metapneusovirus da mai masaukin mutum.

## Yaduwar cututtuka
HMPV tana da alhakin kashi 12% na cututtukan cututtuken numfashi a cikin yara masu lafiya a asibitin asibiti na Amurka  da kashi 15% da 8% na shari'o'in (bisa ga haka) na cutar huhu da aka samu a cikin al'umma wanda ke buƙatar asibiti a cikin yara a ƙarƙashin shekaru 5 a Amurka a cikin 2010-2012. Ana rarraba kwayar cutar a duk duniya kuma, a yankuna masu matsakaici, tana da rarrabawar yanayi gabaɗaya bayan RSV da ƙwayoyin cuta na mura a ƙarshen hunturu da bazara.   Nazarin Serologic ya nuna cewa tun yana da shekaru biyar, kusan dukkanin yara a duk duniya sun fallasa kwayar cutar.    Duk da kusan kamuwa da cuta a duniya a lokacin farkon rayuwa, sake kamuwa da cutar ya zama ruwan dare a cikin tsofaffi yara da manya.  

HMPV may cause mild upper respiratory tract infection (e.g., the common cold). However, premature infants, immunocompromised persons, and older adults >65 years  are at risk for severe disease and hospitalization. In some studies of hospitalizations and emergency room visits, HMPV is nearly as common and severe as influenza in older adults. HMPV is associated with more severe disease in people with asthma and adults with chronic obstructive pulmonary disease (COPD). Numerous outbreaks of HMPV have been reported in long-term care facilities for children and adults, causing fatalities.

Ƙungiyar genomic ta HMPV tana kama da RSV;  duk da haka, HMPV ba ta da kwayoyin halitta marasa tsari, NS1 da NS2, kuma HMPV antisense RNA genome ya ƙunshi firam ɗin karantawa guda takwas a cikin tsarin jinsin ɗan adam daban-daban fiye da RSV (wato 3'-N-P-M-F-M2-SH-G-L-5').  HMPV yana da kama da kwayoyin metapneumoviruses na Avian A, B kuma musamman nau'in C. Binciken phylogenetic na HMPV ya nuna wanzuwar manyan layin kwayoyin halitta guda biyu da ake kira subtype A da B dauke da su a cikin ƙananan ƙungiyoyi A1/A2 da B1/B2 bi da bi.  Genotyping dangane da jerin kwayoyin halittar F da G sun nuna cewa subtype B yana da alaƙa da ƙara tsawon lokacin tari da haɓaka tsarin numfashi na gabaɗaya idan aka kwatanta da HMPV-A.

## Tsarin rayuwa da haifuwa
hMPV an kiyasta yana da lokacin shiryawa na kwanaki 3-6 kuma galibi yana aiki sosai a lokacin hunturu da lokacin bazara a cikin yanayin yanayi mai zafi, tare da yanayin RSV da mura kuma yana iya ba da damar kamuwa da cuta maimaituwa.  Tun daga 2012 [sabuntawa], hMPV da sake zagayowar sa ba a fahimta sosai ba.  An yi nazarin wasu daga cikin manyan matakai na sake zagayowar hMPV tare da gwaje-gwajen da suka danganta da yanayin yanayin rayuwa na hoto ko bidiyo mai zagaya yanar gizo da sauri da kuma matakan haifuwa na sauran dangin Paramyxoviridae..

Mataki na farko na sake zagayowar hMPV shine haɗewa da tantanin halitta, musamman Kwayoyin epithelial na hanyar numfashi, ta amfani da furotin G. Wannan furotin G yana ƙunshe da yankin hydrophobic wanda ke aiki a matsayin peptide na siginar da ba a rufe shi ba da kuma membrane anchor don sauƙaƙe ɗaurewa; duk da haka, saboda Kwayoyin cuta masu haɗuwa waɗanda ba su da furotin G har yanzu suna iya maimaitawa a cikin vitro da in vivo, da alama cewa haɗewa ta hanyar furotin G ba a buƙata don sauran sake zagayowar maimaitawa.

Na gaba a cikin sake zagayowar shine haɗuwa da kwayar cuta da membrane wanda mai yiwuwa furotin F ne ke shiga tsakani. Kodayake tsarin haɗuwa yayi kama da na sauran dangin Paramyxoviridae kuma ya haɗa da canje-canje na furotin F, tsarin hMPV ba ya dogara da furotin G don haɗuwa kamar membobinta na iyali, yana nuna daidaituwa tare da ra'ayin da aka ambata a baya cewa furotin G ba lallai ba ne don matakai na gaba na sake zagayowar hMPV. An tabbatar da aikin haɗuwa na furotin F ta hanyar ikonsa na ɗaurewa ga ƙwayoyin ƙwayoyin ta hanyar integrin αvβ1 ta amfani da Arginine-Glycine-Aspartate (RGD), wanda aka yi hasashen shine abin da ke haifar da abubuwan haɗakar membrane.

Babban bambanci tsakanin hMPV da sauran hanyoyin haɗin ƙwayoyin cuta na Paramyxoviridae ko da yake shi ne cewa hMPV's fusion events faruwa a acidic pH matakan yayin da sauran ƙwayoyin cuta 'fusion events faruwa a tsaka tsaki pH matakan;  duk da haka, ana buƙatar ƙarin bincike a wannan yanki don samun ƙarin fahimtar abin da ya bambanta game da tsarin haɗin hMPV da kuma dalilin da ya sa.  Ko da yake takamaiman aikinsa ba shi da tabbas, kasancewar SH glycoprotein ba ya bayyana yana da wani tasiri akan kwafin motsin motsa jiki, tasirin cytopathic, ko samuwar hMPV..

Bayan hadewa, kwayar ribonucleoprotein (RNP) mai dauke da kwayar cutar kwayar cutar RNA (vRNA) wacce ke dauke da kwayar cutar kwayar cutar kwayar cutar kwayar cuta ana fitar da ita zuwa cikin cytoplasm kuma tana aiki azaman samfuri na mRNA da haɗin gwiwar cRNA na antigenomic.[1]  Daga nan, yawancin iliminmu game da kwafin hMPV an samo su ne daga abin da muka riga muka sani game da RSV da sauran ƙwayoyin cuta na Paramyxoviridae, gami da cewa jagora da jerin tirela a cikin genome suna da wani ɓangare na haɓakawa kuma suna aiki azaman masu tallata rubutu.[1]  Mun ga cewa sunadaran N, P, da L sun rabu da vRNA kuma suna ɗaure juna don samar da hadaddun polymerase don haka RNA na genomic zai iya aiki azaman matrix don kwafin hoto da kwafi a cikin cytoplasm..

Mataki na ƙarshe a cikin tsarin kwafi na hMPV wanda yake da tabbas tabbas shine tafiya na ambulan glycoproteins (F, G, da SH) zuwa yankuna na tarawar membranous ta hanyar kayan aikin Golgi da za a fallasa su a saman ƙwayoyin cutar.  RNA da haɗin sunadaran ƙwayoyin cuta ba su da tabbas kuma suna buƙatar ƙarin bincike..

## Kwayar cuta
HMPV yana kamuwa da ƙwayoyin epithelial na iska a cikin hanci da huhu. Ana tunanin HMPV yana haɗe da tantanin halitta ta hanyar glycoprotein (G) furotin hulɗa tare da heparan sulfate da sauran glycosaminoglycans. HMPV fusion (F) furotin yana ƙunshe da RGD (Arg-Gly-Asp)  wanda ke shiga RGD-binding integrins a matsayin masu karɓar sel,    sannan ya shiga tsakani da haɗuwa da membrane na tantanin halitta da ambulaf ɗin kwayar cuta a cikin salon pH mai zaman kansa, mai yiwuwa a cikin endosomes. HMPV sa'an nan kuma yana haifar da martani na chemokines da cytokines kamar IL-6, IFN-alpha, TNF-alpha، IL-2, da kuma sunadarai masu kumburi na macrophage, wanda hakan ke haifar da peribronchiolar da perivascular infiltration da kumburi.

## Binciken

Gano HMPV ya dogara da fasahar sake fasalin polymerase (RT-PCR) don fadada kai tsaye daga RNA da aka cire daga samfurori na numfashi. An yi amfani da wasu hanyoyin da suka fi dacewa don gano HMPV ta hanyar hanyoyin da suka shafi nucleic acid kuma waɗannan sun haɗa da:

# gano antigen na hMPV a cikin ɓoyewar nasopharyngeal ta hanyar gwajin rigakafin rigakafi
# amfani da immunofluorescence staining tare da monoclonal antibodies don gano HMPV a cikin nasopharyngeal secretions da shell vial al'adu
# Gwaje-gwaje na immunofluorescence don gano takamaiman magungunan rigakafi na hMPV
# amfani da Magungunan rigakafi na polyclonal da keɓewa kai tsaye a cikin ƙwayoyin halitta.

Kodayake an fara gano hMPV kuma an gano shi a cikin shekara ta 2001, binciken serological ya nuna cewa hMPV, ko dangi na kusa da shi, ya riga ya bazu aƙalla shekaru 50. Daga wannan bayanin, a bayyane yake cewa kwayar cutar ba kawai ta "tsalle" daga tsuntsaye ba, ko wasu tankunan dabbobi, zuwa mutane jim kadan kafin gano ta.

Ya zuwa 2022, kamuwa da cuta mafi girma daga hMPV a arewacin arewacin yana cikin ƙarshen hunturu da farkon bazara, amma ana iya samun sa a duniya a duk faɗin nahiyoyi  kuma rarraba sa yana da rikitarwa sosai kuma yana da ƙarfi.  Masu bincike sun gano cewa hMPV galibi yana cikin gida kuma yana iya bambanta sosai daga al'umma zuwa al'umma, yana ba da damar yiwuwar damuwa a wuri ɗaya shekara guda ya zama mafi kama da damuwa a wani wuri daban a shekara mai zuwa.

An rubuta wannan sabon abu tare da kwayar cutar a Ostiraliya a cikin 2001; a Faransa a cikin 2000 da 2002; a Kanada a cikin 1999, 2000, 2001, da 2002; A Isra'ila a cikin 2002; kuma a cikin Netherlands a cikin 2001 duk suna da alaƙa sosai bisa ga jerin kwayar F. Akwai akalla manyan nau'ikan halittar hMPV guda biyu (A da B) waɗanda ke yawo a lokacin barkewar al'umma kuma kowane nau'in halittar yana da nasa biyu,  amma a yanzu, da alama babu wani nau'in da ya fi rinjaye wasu kuma babu wani daga cikinsu da aka sani da haifar da matakan tsananin tsanani. 

HMPV yana yiwuwa yaduwa daga masu kamuwa da cuta zuwa wasu ta hanyar 1. ɓoye daga tari da atishawa, 2. kusancin mutum (misali tabawa, girgiza hannu, da dai sauransu), da 3. taɓa abubuwa da ƙwayoyin cuta a kansu sannan kuma taɓa bakinka, hanci, ko idanu.  A wasu gwaje-gwajen alluran rigakafin, masu bincike sun lura da yadda kwayar cutar parainfluenza na mutum mai raye-raye wacce ke dauke da kwayoyin hMPV F na iya haifar da takamaiman rigakafin hMPV kuma yana iya kare dabbobin gwaji daga hMPV..

Another similar study demonstrated how a chimeric bovine/human parainfluenza virus 3 expressing the hMPV F gene allows for neutralizing antibodies against both parainfluenza and hMPV. These experiments have several limitations, including their small-population animal models. Overall, while vaccines and antiviral therapy treatments are in the works, the biggest difficulty that researchers face  is the limited data available about the development of hMPV in the natural host.

## Rarraba
Wataƙila yaduwar tana faruwa ne ta hanyar hulɗa da ɓoyayyun ɓoyayyen da aka gurbata, ta hanyar droplet, aerosol, ko fomite vectors. An bayar da rahoton kamuwa da cututtukan asibiti tare da metapneumovirus na mutum. An nuna cewa HMPV yana zagayawa a lokacin faduwa da watanni na hunturu tare da sauyawa na nau'i ɗaya a kowace shekara.

## Magani
Babu wani magani ga mutane da aka sani tun daga shekara ta 2008.  Ribavirin, magani da aka yi amfani da shi don magance RSV, ya nuna tasiri a cikin samfurin dabba.

Kamfanin samar da magunguna na Amurka Moderna ya gudanar da gwajin asibiti don rigakafin modRNA na dan takarar rigakafin metapneumovirus. Ya zuwa watan Oktoba na shekara ta 2019, dan takarar rigakafin ya wuce matakin I, tare da rahotanni cewa rigakafin yana da haƙuri sosai a duk matakan sashi a cikin watanni biyu, kuma yana haifar da amsawar rigakafi wanda ke haɓaka samar da Magungunan rigakafi.

## Juyin Halitta
An fara bayar da rahoton metapneumovirus na mutum a cikin 2001 da kuma metapneusovirus na tsuntsaye a cikin shekarun 1970. Akwai akalla zuriya huɗu na metapneumovirus na mutum - A1, A2, B1 da B2. An raba kwayar cutar metapneumovirus ta Avian zuwa rukuni huɗu - A, B, C da D. Kimanin Bayesian ya nuna cewa kwayar cutar ta mutum ta fito ne tsakanin 1875 da 1889 kuma ta rabu da kwayar cutar avian a kusa da 1800. 

## barkewar cutar ta 2024-2025
Cibiyar Kula da Cututtuka da Cututtuka ta kasar Sin ta buga bayanai da ke nuna cewa kamuwa da cututtukan numfashi ya karu sosai a cikin mako na 16 zuwa 22 ga Disamba 2024;  An danganta cutar metapneumovirus ta mutum zuwa kashi 6.2 na ingantattun gwaje-gwajen cututtukan numfashi da kashi 5.4 na asibitocin cututtukan numfashi a China, fiye da COVID-19, rhinovirus, ko adenovirus.  Kan Biao, shugaban cibiyar yaki da cututtuka masu yaduwa ta kasar Sin CDC, ya sanar da cewa, adadin HMPV a tsakanin yara masu shekaru 14 zuwa kasa da kasa na karuwa a kasar Sin.

## Bayanan da aka ambata