CINXE.COM

<!DOCTYPE html><html lang="en-US"><head><title>Just a moment...</title><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><meta http-equiv="X-UA-Compatible" content="IE=Edge"><meta name="robots" content="noindex,nofollow"><meta name="viewport" content="width=device-width,initial-scale=1"><style>*{box-sizing:border-box;margin:0;padding:0}html{line-height:1.15;-webkit-text-size-adjust:100%;color:#313131;font-family:system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica Neue,Arial,Noto Sans,sans-serif,Apple Color Emoji,Segoe UI Emoji,Segoe UI Symbol,Noto Color Emoji}body{display:flex;flex-direction:column;height:100vh;min-height:100vh}.main-content{margin:8rem auto;max-width:60rem;padding-left:1.5rem}@media (width <= 720px){.main-content{margin-top:4rem}}.h2{font-size:1.5rem;font-weight:500;line-height:2.25rem}@media (width <= 720px){.h2{font-size:1.25rem;line-height:1.5rem}}#challenge-error-text{background-image:url(data:image/svg+xml;base64,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);background-repeat:no-repeat;background-size:contain;padding-left:34px}@media (prefers-color-scheme:dark){body{background-color:#222;color:#d9d9d9}}</style><meta http-equiv="refresh" content="120"></head><body class="no-js"><div class="main-wrapper" role="main"><div class="main-content"><noscript><div class="h2"><span id="challenge-error-text">Enable JavaScript and cookies to continue</span></div></noscript></div></div><script>(function(){window._cf_chl_opt={cvId: '3',cZone: "publications.waset.org",cType: 'non-interactive',cRay: '9135ce2009613e14',cH: '9PVM7pJIeclgR4Wfnh_Sq4vIdjyDrfBbC2Ijb_G_ctM-1739795599-1.2.1.1-c.piRZWsPfJKA4fk7DmMMMxkuVaMBLFSY8LTfeEmV5Acy7zjHeiV6X6R8ek4NV5j',cUPMDTk: "\/abstracts\/search?q=coronavirus&__cf_chl_tk=d7YQLv6KeJ7X2tJjeXh41PEzNPQJv2qbm3Rye8j6pQE-1739795599-1.0.1.1-GkGLaJufy9cVBBQYOMPIN3wzuMeSmRscubPQOzNwE_w",cFPWv: 'b',cITimeS: '1739795599',cTTimeMs: '1000',cMTimeMs: '120000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "",fa: "\/abstracts\/search?q=coronavirus&__cf_chl_f_tk=d7YQLv6KeJ7X2tJjeXh41PEzNPQJv2qbm3Rye8j6pQE-1739795599-1.0.1.1-GkGLaJufy9cVBBQYOMPIN3wzuMeSmRscubPQOzNwE_w",md: "hyewzkj202ITagqzD3QGogWxfjTm3gsD46a5fXIo8bQ-1739795599-1.2.1.1-7UXK_3PlIJN3bS3ckOmCElF8Xnx6f4d6CUBsHmU80oEEHIRXW9JfUttuexUPgjEX6CL4f0qUe.N2xdkk43XjObRFXgukB1HV0OVX436jE75k0J_iKqFfcrltfngoTrvncrxkGpOxQvsPOZ2Tzfk86j3F3aD5DErPra5DkMM4ekoa6BLodDE4NC94aMZJasc.IMjEMn4SH5_4jAI2kmP7MJwZK_l511PS_59VLonCWk0ENLFsncwI7yHHSbrPw9R_MBint06hjbD3mqX.A_ZbWAalRPRX8rvA4rsMxfVK8MMzfxM_J8UfoDhZX0xIUr1hEsqclyKw3ErPgWJbWtC5.0P1w9aY37tgR78MEpkh.yAuagHqzzXiSkIdrL5L7fL2XIdyoyAauqIKVq3hCoccbYfGGXfYvYDYwWx_0DELcn.4SKs.vc7QG4s9ihxQHAV0vNksDISQ3qNu4efNTFx_.beqRSRscsDAnff7aHkdT5naVDbgGk8oDXA0TrUOVXISzGwxlvzvg2P6JIzJIePRCpg9xxAiimMcAYspuHU6R_j56qgzSRUbHsDsaOItnbVJwTUVvg2dOKxQoteYqeksLxXBugrrjhOq0CaEXuVIXeBT_wFjKQtK4Jp429BoLFaVArjPExGYqLqWIya1_8ehHq5AgqDj059K5q5PjBzCymr08dWrfav4bSJSXMrvzstRce4DIxjM0A5wTfh5IGg0bzkx7ILqyJVuHJB9MrORzUqMMS5V7kt3QngUvxnEsKStbIaMRIJdgsdZta1oW6JQowvCHyEm1Nds9OWjGQYbaFruHlMnLlGIaqIeEDYP_sdbqA8lb1phBUg8Mu9j54L.l79cPnRfWUp5yDqZ6yZ20uy8ZPORwk3mJkqhFjMW9s.o.uEQ2c8YmrjNvcxsZPsz3gCeL.12kQ1fXIiCNMgg8hMJxiiU2bX6O7i0WLekaJQVu_JkNxfMvh1UUmLcCPOVTcGlLN_ymgcIKcqAi7klL1NnbSuVyqpqH76LsTYqAQHM0QILkHp9exttQar.O.MEQrwCycFDdTJKfhLTNWVGze7I4AI5BLJi6Ky.fOSRCgf2bwv_HLKrYLNQGddu8.3rOmRK8Iq1UKGxrRBOBMVixjIACNPX_OiJf0gPcUyCV1zlzDMwjXAucDh9oCv8ksCZGON_UE0GNjSSyS4z131XHU2K90Bcpv44M0nAhPRJBCuZxmmSSrVIondz1iRwSIuOaUPXmOuLWj0YGd6KdQA66lIJqtgET8DdozRnEuIE6923ZdllVCZbf8bDTzEjxsrlR6IfqHd760VZda3y4d_e0ITt5Qf6UnCX9Ywsu6eTUMiUj5KJpjlDIMSy7oTYPY8G5YwO.5ju2d2bU1_veH6zwsX1bSryhKkqQ723nG1Em5lVXtaEENEFhHcLPrFMokYZmpB2yx6jDmXGQv1gaEyxyip22DqtNu.Ry77B9XcSu0.WLKdINxRJUpeQ5qaXlTysbYUEOmwvTE3PMqurtHgCRxaneDaOLmF7jz_QxXiZbvNjQrSEpYOPMdmQbKcSmlak9blOj73LC6tI2aRvB_CwDuRvVt2NkR8RO.9z4NkTlF.nV9OEV_OEv.zS8Cq5TNkp1dwO1pQBNKHJ5i2VdtupQUi0TUT.F7fab83YtMj313X6tCb_kSA1H3Ly22eQp5MxMH_C8skSo9_8WbOEQlDnN0btHNKLz6wygIZ2YAxxFW9fMrKjEfapRzayw6MxnAw8Ah039wWtIgQOZLCs11xOxS.gLEMDrjAtxvt0vlD8r4WZhydWGmMeSzBZXyVEulr6zQdW84y9_r_bozX.5qZI7hSDdCW3nxlW1dHA.CrPYDAASL6oDiUtUtTUu7EguZi_I5puS6sNLJhSa0QPm30ll2OzN9uahV_Iq9.eK0XwnoqtycMTtDXMKpr5lR3ALSrptw",mdrd: "zL77RI5GrrAIdP4xMcd.YFiOi6IP_eqk7tT2y4GGw5U-1739795599-1.2.1.1-dYKn8cDbgx5NoXfm0DIotmFnPGW_qpSNKhWWvtr38A5xv.MXEfUGpK5.wMgLEeo29pai6H894kVAS_vNAmiV9wXU6hjqymdHMy7IIR_1sQlqp1y_Py8lV_A22MTHFPp3a3WlxhpSSN4x64No7YcfQcAQiawmihrV.f4KcsoQ44YgnEtSp0xUFRSGvBwxGtq3cDOACVgE3BD3eWahQ_j7f2saLRmTuPQn42wjEqrenYNHbza7gG6efwR9NceODYkDQqDvFP5jLmgDiNY1jGTICLhfnz8qURl.5hvIj0Ai6oqSwtbYI4MwQ_IHw3.UgRIJ1kGX6oUQnjdlex3aKAw7gclKe67nLW3mgMvGPNTXDgCFrLNQyKClBk_1C_pDfz7tpgNbZO5bXpIwTO5w3BPN2B0zutrh_ViUbBeSMwXkx9_lVlyM44jftgk3iyOBsdfqljFhjQ68MYgeCDBK_YekbpDPTG4X2rLix3PjmfGnszh9cMwyHHd5U_CQ_Po1ql8yQ5QPcWIKBWRBLJEVCYJqG1OhljDz31G5WE9VTZjKTZmRc400SA.bKxTVN_b9F0haWTYRa6OjNpm2kAWQvzlS2Yja9CRU0PfuE7hSWlOx8T7_wMOcxX5E4zqIOB1ILZgAwejE8d88kxNRdlSTyFaClv68mcxUFO9xFgM7XPkaqaKWi_kbvaOi5Y0L.uCHPwYxrYw7NJ4gTZz4OGFw1TPMjaUZcS7Ftr28fFHNElMn2gnejq3AW47nhY4CQmNOxbbPoi1Z6VCI1CI0JtsJJSFsoIPBDdu8fRabtCrd2U01FlDOCvuWye9nEFqpG0D7Vq8oXV8LPPGyRlYkK6l5kH4gwZAUDm7knxZqJ4CS.N_Vn8WIDDAKVis0YNhBtyH2aN07Utq9Tu_urzHz16EnKyKqTUtEovD5Xv_iuBw_wvob5SftXOf8_yYdTcK8HQCSb_x5F4mzYwBaK2zU676hzqX0Tj5mglK56lNXVKyO4dO8899IUcZsv43gejxn56mdpTSitgHhL5xICvBSO.uqzrBWHU4Ve7Leg1WWB7F_n6r113j1vkpDWQX9Wnp_NJy0F.5gqIro_LhSBOv8iXjbOL3tta74LtDxvnU6N5L4NZL6dhYEFx9cldjeQEyqA2giLN_BwJ4nyuBjNHu1SqaBV9BJOr2d2jd8WTmidb6ZOFI3ZmpZj1OSlIqz4z92u5taN_cABMqxjnW4U4uncmotnD1bzHMTckcKYI8vCfQuBcUzuHYz9BfldKGEhD11WCfWYSY8SzK2KJ.D2hMRZ9O.BN1XGzV9dy2qazKkbFsMQDiyhVa7qFd1s66710jxscOWGa7HU5qmTxcpx2CLQ687mDsg6yyQSZlsm2ucc5gDpALbtTeOFOerPbpBIqL7KO0QJfErJiSN6u0zQKoZCMuwI7hBxpqwG1wFV5y3lmmv0bHOOKG65QbzY92njGgfQPLvQ2mVFaQTeD6r18ueoJv8OmRAZBITz4Q3J9mKj4Mwf5.Qvt6rjWOV9ut_8wFnhuDmvTKAy9AGSGvq7AFtvVqShtJm32SOYoIfkbkVeqPtqzaFDJ6IPUBHpO8pqIo2qCPCoJHjbjcpTnQzKlVv0diKCn6QKL6BnQz9Tg.qyh0tnHPICl_cC1MG4HED01wycOOm3SOZGrU5x.7wO5MfwiFVAHXbRzyx1IUq3LFz8.Axc6RztxVYxO8UphAnEc4eP_KPN8S.tHcWo88L7iAPVUBrh5ONsfvYQb8C18AzY8MhM_rg5NVuH6zp13Q_frzAHYegQrJu18YL5OJSxD0bPw6eMbhW5WcieD3vKn9I1KpnfJGjUM3._d3mRuv_mRLKCE5ltFSXlK7UtlrLm6sb8wkkbZQY5BniYdITi_WDrg3RaGlyMl05_5GRPEXPKClV92vLetWaTZjNARzbIeovrMghE9dvgiY5I6_EiEe4t03ITp9zIQ7XOyFPp2mZE_ZITqH8JYtq"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/b/orchestrate/chl_page/v1?ray=9135ce2009613e14';window._cf_chl_opt.cOgUHash = location.hash === '' && location.href.indexOf('#') !== -1 ? '#' : location.hash;window._cf_chl_opt.cOgUQuery = location.search === '' && location.href.slice(0, location.href.length - window._cf_chl_opt.cOgUHash.length).indexOf('?') !== -1 ? '?' : location.search;if (window.history && window.history.replaceState) {var ogU = location.pathname + window._cf_chl_opt.cOgUQuery + window._cf_chl_opt.cOgUHash;history.replaceState(null, null, "\/abstracts\/search?q=coronavirus&__cf_chl_rt_tk=d7YQLv6KeJ7X2tJjeXh41PEzNPQJv2qbm3Rye8j6pQE-1739795599-1.0.1.1-GkGLaJufy9cVBBQYOMPIN3wzuMeSmRscubPQOzNwE_w" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>