Content uploaded by Stefan Reichenberg
Author content
All content in this area was uploaded by Stefan Reichenberg on Feb 25, 2020
Content may be subject to copyright.
Vox Sanguinis (2020)
ORIGINAL PAPER ©2020 International Society of Blood Transfusion
DOI: 10.1111/vox.12888
Inactivation of three emerging viruses –severe acute
respiratory syndrome coronavirus, Crimean–Congo
haemorrhagic fever virus and Nipah virus –in platelet
concentrates by ultraviolet C light and in plasma by
methylene blue plus visible light
Markus Eickmann,
1,†
Ute Gravemann,
2,†
Wiebke Handke,
2
Frank Tolksdorf,
3
Stefan Reichenberg,
3
Thomas H. M€
uller
2
&
Axel Seltsam
2
1
Institute for Virology, Philipps University Marburg, Marburg, Germany
2
German Red Cross Blood Service NSTOB, Springe, Germany
3
Maco Pharma International GmbH, Langen, Germany
Received: 27 September 2019,
revised 18 December 2019,
accepted 18 December 2019
Background Emerging viruses like severe acute respiratory syndrome coronavirus
(SARS-CoV), Crimean–Congo haemorrhagic fever virus (CCHFV) and Nipah virus
(NiV) have been identified to pose a potential threat to transfusion safety. In this
study, the ability of the THERAFLEX UV-Platelets and THERAFLEX MB-Plasma
pathogen inactivation systems to inactivate these viruses in platelet concentrates
and plasma, respectively, was investigated.
Materials and methods Blood products were spiked with SARS-CoV, CCHFV or
NiV, and then treated with increasing doses of UVC light (THERAFLEX UV-Plate-
lets) or with methylene blue (MB) plus increasing doses of visible light (MB/light;
THERAFLEX MB-Plasma). Samples were taken before and after treatment with
each illumination dose and tested for residual infectivity.
Results Treatment with half to three-fourths of the full UVC dose (02 J/cm
2
)
reduced the infectivity of SARS-CoV (≥34 log), CCHFV (≥22 log) and NiV (≥43
log) to the limit of detection (LOD) in platelet concentrates, and treatment with
MB and a fourth of the full light dose (120 J/cm
2
) decreased that of SARS-CoV
(≥31 log), CCHFV (≥32 log) and NiV (≥27 log) to the LOD in plasma.
Conclusion Our study demonstrates that both THERAFLEX UV-Platelets (UVC)
and THERAFLEX MB-Plasma (MB/light) effectively reduce the infectivity of
SARS-CoV, CCHFV and NiV in platelet concentrates and plasma, respectively.
Key words: ultraviolet light, methylene blue, pathogen inactivation, plasma, plate-
let concentrates.
Introduction
There is a large group of emerging viruses known to be
occasionally transmitted by blood or to have properties
suggesting their transmissibility by this route. These
pathogens include severe acute respiratory syndrome
coronavirus (SARS-CoV), Crimean–Congo haemorrhagic
fever virus (CCHFV) and Nipah virus (NiV), which have
been identified by the World Health Organization (WHO)
as major infectious threats with the potential to cause a
global pandemic [1–3].
There are different pathogen inactivation techniques
that have been developed to reduce or eliminate the
Correspondence: Axel Seltsam, German Red Cross Blood Service NSTOB,
Institute Springe, Eldagsener Strasse 38, 31832 Springe, Germany
E-mail: axel.seltsam@bsd-nstob.de
†
Contributed equally to this work.
1
threat of infectivity from known and emerging transfu-
sion-transmissible agents [4]. THERAFLEX UV-Platelets
(Macopharma, Tourcoing, France) is a novel method for
pathogen inactivation treatment of platelet concentrates
(PCs) [5–7]. This purely physical system is based on short-
wave UVC light, which penetrates the fluid of PCs and
inactivates micro-organisms and leucocytes by damaging
nucleic acids. THERAFLEX MB-Plasma (Macopharma) is a
photodynamic pathogen inactivation procedure for treat-
ment of plasma [8,9]. Plasma units derived from single
blood donations are illuminated with visible light in the
presence of the phenothiazine dye methylene blue (MB).
When plasma is MB/light-treated, singlet oxygen is gen-
erated, which leads to the destruction of viral nucleic
acids. The MB/light-based method is in routine use in
Europe for about 17 years [10].
Both pathogen inactivation systems have been tested
in vitro to be effective against many different types of
viruses, including emerging viruses such as West Nile
virus and yellow fever virus [6,8,9,11–19]. In this study,
we investigated the capacity of THERAFLEX UV-Platelets
and THERAFLEX MB-Plasma systems to inactivate the
emerging viruses SARS-CoV, CCHFV and NiV in PCs and
plasma, respectively.
Materials and methods
Selection of donors
Selection of volunteer donors was based on local standard
practices. Only regular blood donors that fulfilled the
requirements for blood donation and had given their
informed consent approved by the local ethics committee
were included in the study.
Blood component preparation
Plasma-reduced PCs in platelet additive solution SSP
+
(Macopharma) were prepared from pools of five buffy
coats as previously described and were stored under agi-
tation at 22 –2°C [14]. The target specifications of the
PCs were a platelet concentration of approximately
1x10
9
/mL and a plasma content of approximately 35% in
accordance with Macopharma’s specifications for UVC
treatment of PCs. Air was removed from all plasma units
and PCs.
Pathogen inactivation methods
Pathogen inactivation of PCs was performed using the
THERAFLEX UV-Platelets system (Macopharma) according
to the manufacturer’s instructions as described previously
[14]. All PCs were irradiated with UVC light to a total dose
of 02 joules per square centimetre (J/cm
2
) with constant
vigorous agitation to ensure uniform treatment [6].
Pathogen inactivation of plasma units was performed
using the THERAFLEX MB-Plasma system (Macopharma)
as described previously [14]. Plasma for pathogen inacti-
vation was processed by filtration for leucodepletion,
addition of MB and subsequent illumination with visible
light to a total dose of 120 J/cm
2
according to the
instructions of the manufacturer for this system [20]. The
MB removal step, an integral processing step in routine
use of the THERAFLEX MB-Plasma system, was omitted
for exclusive analysis of the virus inactivation effects of
illumination.
Spiking experiments
Virus titres were determined by assessing for virus-induced
changes in morphology (cytopathic effects) of indicator
cells and calculated according to the Spearman–K€
arber
method and expressed as the log of the 50% tissue culture
infectious dose (log TCID50) [14,21,22]. Titration was per-
formed at the initial sample dilutions at which no cytotoxi-
city of indicator cells was observed. The effectiveness of
virus inactivation was calculated as the log reduction fac-
tor (RF) using the formula RF =log
10
A
0
–log
10
A
n
, (R,
reduction factor; A
0
, spiked total virus load before treat-
ment; and A
n
, total virus load after treatment). The overall
reduction factor was expressed as the sum of RFs for all
steps. The limit of detection (LOD) of the assay was defined
as the lowest TCID
50
achievable at non-cytotoxic sample
concentrations.
SARS-CoV, strain Frankfurt 1 [23], was grown and
assessed in Vero E6 cells (ATCC CCL-22), CCHFV, strain
Afg09-2990 [24], was propagated and assessed in Huh7
cells (JCRB 0403), and NiV, strain Malaysia [25], was
grown and assayed in Vero 76 cells (ATCC CRL-1587).
For preparation of the virus stocks, viral supernatants
were collected on days 2–4 of cell culture, when a cell
confluence of approximately 80% was achieved, cen-
trifuged, aliquoted and frozen at -80°C until further use
in spiking experiments.
PCs (volume: 375 ml; n=2 per virus) and plasma
units (volume: 315 ml; n=2 per virus) were spiked 1:10
with supernatant of each virus and treated with UVC and
MB/light, respectively. After spiking, PCs and plasma
units were still within the specifications of the respective
pathogen inactivation method. The light doses were
applied incrementally until the full light doses of each
treatment were achieved. After each process step, samples
were collected and serially diluted for virus titration. In
order to test for intrinsic virus inactivation of the blood
product, reference samples were collected from each bag
before pathogen inactivation treatment, stored at room
©2020 International Society of Blood Transfusion
Vox Sanguinis (2020)
2M. Eickmann et al.
temperature and tested at the end of the experiments to
account for any intrinsic virus inactivation by the blood
product.
Results
The results of the infectivity assays demonstrated that
UVC irradiation and MB/light dose-dependently inacti-
vated SARS-CoV, CCHFV and NiV in plasma-reduced PCs
and plasma units, respectively. In PCs, at half of the full
UVC dose (01 J/cm
2
) SARS-CoV and CCHFV infectivity
levels were below the LOD, while at three-fourth of the
full UVC dose (015 J/cm
2
) also NIV infectivity levels
were below the LOD (Table 1). Thus, virus reduction fac-
tors ≥34 for SARS-CoV, ≥22 for CCHFV and ≥43 for
NiV were achieved with the UVC-based pathogen inacti-
vation system in PCs.
In plasma, already at one-fourth of the full light dose
(30 J/cm
2
) SARS-CoV, CCHFV and NiV were inactivated
to levels below the LOD (Table 2). These results corre-
spond to virus log reduction factors of ≥31, ≥32 and
≥27 that were achieved by MB/Light treatment for
SARS-CoV, CCHFV and NiV, respectively, in plasma.
For SARS-CoV, we observed a loss of infectivity of
about 1 log lower after spiking in some cases. This signif-
icant loss of infectivity was probably caused by non-
specific innate immune factors that neutralize viruses in
plasma [23,24]. However, virus titres did not further
decrease in controls during the course of the experiments.
In particular, there were no significant differences
between load and reference samples, indicating that the
observed virus inactivation was solely caused by the
treatment with UVC and MB/light.
Discussion
A major argument for using pathogen inactivation tech-
nologies to treat blood components is that they support a
proactive approach providing more generalized protection
against new and emerging infectious agents which con-
tinuously challenge the safety of the blood supply. The
conventional reactive approach to wait until the threat
from an emerging transfusion-transmitted agent has been
identified before responding by modifying donor screen-
ing programmes takes time and, ultimately, the response
may not be quick enough to prevent the transfusion of
contaminated blood products. Because there are hundreds
of known emerging or re-emerging human pathogens
[26], the manufacturers of pathogen inactivation methods
are required to continuously test the inactivation capacity
of their systems for new infectious agents.
In this study, the inactivation efficacy of UVC and MB/
light was for the first time tested against CCHFV and NiV
Table 1 Inactivation of SARS-CoV, CCHFV and NiV in platelet concentrates by THERAFLEX UV-Platelets
a
Light dose (cumulative)
SARS-CoV CCHFV NIV
Bag 1 Bag 2 Bag 1 Bag 2 Bag 1 Bag 2
log
10
TCID
50
/ml log
10
RF log
10
TCID
50
/ml log
10
RF log
10
TCID
50
/ml log
10
RF log
10
TCID
50
/ml log
10
RF log
10
TCID
50
/ml log
10
RF log
10
TCID
50
/ml log
10
RF
Virus stock 72–0169–0368–0263–0175–0274–03
Spiked bag 58–0360–0252–0346–0262–0365–02
005 J/cm
2
27–033130–043024–012824–012139–032341–0224
01 J/cm
2
≤24≥34≤24≥36≤24≥29≤24≥22≤19≥4320–0146
015 J/cm
2
≤24≥34≤24≥36≤24≥29≤24≥22≤19≥43≤19≥46
02 J/cm
2
≤24≥34≤24≥36≤24≥29≤24≥22≤19≥43≤19≥46
Ref. sample 59–02-0159–030154–02-0249–02-0362–03-0163–0202
a
TCID
50
, 50% tissue culture infectious dose; RF, reduction factor; Ref. sample, pretreatment reference sample.
©2020 International Society of Blood Transfusion
Vox Sanguinis (2020)
Inactivation of SARS-CoV, CCHFV and Nipah virus 3
or other members of the Nairoviridae and Paramyxoviri-
dae families. SARS-CoV was also included in the study to
confirm the efficacy of the two pathogen inactivation
systems for coronaviruses, as has previously been demon-
strated for MERS-CoV [14]. The results of this study show
that both pathogen inactivation systems effectively inac-
tivated all three viruses spiked into the PC and plasma
samples, even at light dose increments below the full
doses recommended by the manufacturers. One limitation
of this study is that the number of replicates was small
due to safety constraints –laboratory studies with these
zoonotic viruses must be performed in accordance with
the highest biosafety requirements. In addition, large-vol-
ume plating which would have allowed increasing the
sensitivity of the assay and consequently improving the
log reduction value could not be performed.
SARS-CoV is an enveloped, positive-sense single-
stranded RNA coronavirus. It emerged in 2002 in China
and spread to 29 additional countries and is thought to
be an animal virus that spread to humans from civets
most likely infected by bats [27]. Similar to Middle East
respiratory syndrome coronavirus (MERS-CoV), the main
route of human-to-human transmission of SARS-CoV is
nosocomial transmission. However, transmission between
family members has also been observed, suggesting that
SARS-CoV might continue to spread via transmission by
infected persons returning from affected areas. Transmis-
sion by blood transfusion has not been described yet.
Nevertheless, the high mortality of the disease and the
not yet fully understood transmission mechanisms of
SARS-CoV pose a potential threat to the safety of the
blood supply [27]. Interestingly, the detection of low-level
viremia in asymptomatic patients during an SARS-CoV
outbreak suggests a theoretical risk of transmission via
blood products. As a precautionary measure, the World
Health Organization introduced a recommendation for the
deferral of blood donations from donors potentially
exposed to SARS-CoV, and the Australian Red Cross
Blood Service amended its donor screening questionnaire
to include questions to identify persons with SARS-CoV-
related symptoms [28].
Crimean–Congo haemorrhagic fever virus is an envel-
oped, negative-sense single-stranded RNA virus of the
Nairoviridae family. CCHFV often results in a mild, non-
specific febrile illness but may occasionally cause severe
haemorrhagic disease. This disease was first identified in
the Crimean region of the former Soviet Union in 1944
and is a significant public health concern. CCHFV occurs
across a wide geographic region, including Europe, Asia
and Africa, and may expand into new regions [29]. The
virus is usually transmitted to humans through contact
with infected ticks and animal blood, but it is also trans-
missible from human to human via exposure to infected
Table 2 Inactivation of SARS-CoV, CCHFV and NiV in plasma by THERAFLEX MB-Plasma
a
Light dose (cumulative)
SARS-CoV CCHFV NIV
Bag 1 Bag 2 Bag 1 Bag 2 Bag 1 Bag 2
log
10
TCID
50
/ml log
10
RF log
10
TCID
50
/ml log
10
RF log
10
TCID
50
/ml log
10
RF log
10
TCID
50
/ml log
10
RF log
10
TCID
50
/ml log
10
RF log
10
TCID
50
/ml log
10
RF
Virus stock 74–0271–0265–0360–0275–0275–02
Spiked bag 54–0356–0352–0251–0261–0.2 64–02
30 J/cm
2
≤24≥31≤24≥32≤19≥32≤19≥32≤34≥27≤34≥30
60 J/cm
2
≤24≥31≤24≥32≤19≥32≤19≥32≤34≥27≤34≥30
90 J/cm
2
≤24≥31≤24≥32≤19≥32≤19≥32≤34≥27≤34≥30
120 J/cm
2
≤24≥31≤24≥32≤19≥32≤19≥32≤34≥27≤34≥30
Ref. sample 54–030057–03-0151–020152–02-0162–02-0163–0201
a
TCID
50
, 50% tissue culture infectious dose; RF, reduction factor; Refsample, pretreatment reference sample.
©2020 International Society of Blood Transfusion
Vox Sanguinis (2020)
4M. Eickmann et al.
blood and other body fluids. Although no cases of CCHFV
transmission by blood transfusion have been reported to
date, incidences of hospital-acquired CCHFV infection
due to contaminated medical instruments have been doc-
umented [30]. These cases are strongly reminiscent of the
transmission routes of many other transfusion-relevant
viruses.
NiV is an enveloped, single-stranded negative-sense
virus that belongs to the Paramyxoviridae family. It was
reported for the first time in the Malaysian population in
1998 and reappeared on different occasions in Asia. The
NiV disease spectrum ranges from asymptomatic infection
to acute respiratory illness and fatal encephalitis [31]. NiV
is a zoonotic virus transmitted to humans from animals
such as bats or pigs, but it can also be transmitted through
contaminated foods or directly person-to-person through
close contact with virus-containing body fluids and excre-
tions [32]. The available data, particularly the findings on
viral load in different body fluids, are too limited to pro-
vide a full understanding of its transmission routes [33].
Transfusion has not been implicated as a potential trans-
mission pathway to date. The incubation period of up to
14 days and the occurrence of latent infections with subse-
quent reactivation of NiV months and even years after
exposure suggest that infected persons may be overlooked
by donor screening programmes. However, the potential
transfusion risk may be limited by the fact that asymp-
tomatic and mild NiV infections are rare.
Future studies are needed to determine whether SARS-
CoV, CCHFV and/or NiV can be transmitted through
transfusion. If one or more of these viruses is transfusion
transmissible, its threshold concentration to elicit disease
must be examined to determine whether the capacity of
these pathogen inactivation technologies to inactivate the
respective virus in plasma and PCs is sufficient to prevent
transfusion transmission. Interpreting pathogen load in
relationship to infectivity and inactivation efficacy is
generally a very complex task [34]. When attempting to
do so, it is important to consider that because quantita-
tive polymerase chain reaction (qPCR), the most com-
monly used approach, measures viral load by detecting a
small fragment of the viral genome, the results may not
reflect infectivity and that qPCR usually overestimates the
titre of circulating infectious agents [34]. In contrast,
infectivity assays, which were used in this and previous
studies [5,12–14], determine the inactivation capacity of a
pathogen inactivation method based on intact, functional
viral units. Nevertheless, the log reduction factors
observed in this study and the safety margins calculated
from the inactivation levels achieved using only a frac-
tion of the standard light dose suggest that the THERA-
FLEX UV-Platelets and THERAFLEX MB-Plasma pathogen
inactivation technologies may effectively reduce the
potential risk of SARS-CoV, CCHFV and NiV and related
viruses for platelet or plasma transfusion.
Acknowledgements
We would like to thank Katharina Kowalski for excellent
technical assistance and the staff of the blood collection
and blood preparation departments for their support.
Conflict of interest
FT and SR are employees of Macopharma, manufacturer
and distributor of the THERAFLEX pathogen inactivation
(PI) system. UG, WH, THM and AS received project grants
from the German Red Cross Blood Services and Maco-
pharma for the development of the UVC-based PI technol-
ogy for platelets. ME has no conflicts of interest to disclose.
Author contributions
M. Eickmann designed the study, interpreted the data and
co-wrote the manuscript. U. Gravemann designed the
study, performed the in vitro experiments and analysed
the data. W. Handke performed the in vitro experiments
and analysed the data. F. Tolksdorf interpreted the data
and edited the manuscript. S. Reichenberg interpreted the
data and edited the manuscript. T. H. M€
uller interpreted
the data and edited the manuscript. A. Seltsam designed
the study, interpreted the data and wrote the manuscript.
All authors read and approved the final manuscript.
Funding
This work was supported by the German Red Cross Blood
Services (Deutsche Forschungsgemeinschaft der Blut-
spendedienste des Deutschen Roten Kreuzes) and Maco-
pharma S.A.S.
References
1 Stramer SL, Hollinger FB, Katz LM,
et al.: Emerging infectious disease
agents and their potential threat to
transfusion safety. Transfusion 2009;
49:1S–29S
2 Stramer SL: Current perspectives in
transfusion-transmitted infectious dis-
eases: emerging and re-emerging
infections. ISBT Sci Ser 2014; 9:
30–6
3 Bahar B, Schulz WL, Gokhale A, et al.:
Blood utilisation and transfusion reac-
tions in adult patients transfused with
conventional or pathogen-reduced pla-
telets. Br J Haematol 2019. https://doi.
©2020 International Society of Blood Transfusion
Vox Sanguinis (2020)
Inactivation of SARS-CoV, CCHFV and Nipah virus 5
org/10.1111/bjh.16187 [Epub ahead of
print].
4 Seltsam A, Muller TH: Update on the
use of pathogen-reduced human
plasma and platelet concentrates. Br J
Haematol 2013; 162:442–54
5 Mohr H, Steil L, Gravemann U, et al.:
A novel approach to pathogen reduc-
tion in platelet concentrates using
short-wave ultraviolet light. Transfu-
sion 2009; 49:2612–24
6 Seltsam A, Muller TH: UVC irradiation
for pathogen reduction of platelet con-
centrates and plasma. Transfus Med
Hemother 2011; 38:43–54
7 Kim S, Handke W, Gravemann U,
et al.: Mitochondrial DNA multiplex
real-time polymerase chain reaction
inhibition assay for quality control of
pathogen inactivation by ultraviolet C
light in platelet concentrates. Transfu-
sion 2018; 58:758–65
8 Mohr H, Lambrecht B, Selz A: Photo-
dynamic virus inactivation of blood
components. Immunol Invest 1995;
24:73–85
9 Seghatchian J, Walker WH, Reichen-
berg S: Updates on pathogen inactiva-
tion of plasma using Theraflex
methylene blue system. Transfus
Apher Sci 2008; 38:271–80
10 Politis C, Kavallierou L, Hantziara S,
et al.: Haemovigilance data on the use
of methylene blue virally inactivated
fresh frozen plasma with the Theraflex
MB-Plasma System in comparison to
quarantine plasma: 11 years’ experi-
ence. Transfus Med 2014; 24:316–20
11 Williamson LM, Cardigan R, Prowse CV:
Methylene blue-treated fresh-frozen
plasma: what is its contribution to blood
safety? Transfusion 2003; 43:1322–9
12 Faddy HM, Fryk JJ, Prow NA, et al.: Inac-
tivation of dengue, chikungunya, and
Ross River viruses in platelet concen-
trates after treatment with ultraviolet C
light. Transfusion 2016; 56:1548–55
13 Fryk JJ, Marks DC, Hobson-Peters J,
et al.: Reduction of Zika virus infec-
tivity in platelet concentrates after
treatment with ultraviolet C light and
in plasma after treatment with
methylene blue and visible light.
Transfusion 2017; 57:2677–82
14 Eickmann M, Gravemann U, Handke W,
et al.: Inactivation of Ebola virus and
Middle East respiratory syndrome coron-
avirus in platelet concentrates and
plasma by ultraviolet C light and methy-
lene blue plus visible light, respectively.
Transfusion 2018; 58:2202–7
15 Arnason NA, Johannson F, Landro R,
et al.: Pathogen inactivation with
amotosalen plus UVA illumination
minimally impacts microRNA expres-
sion in platelets during storage under
standard blood banking conditions.
Transfusion 2019; 59:3727–3735
16 Castro E, Girones N, Guerrero N, et al.:
The effectiveness of UVC pathogen
inactivation system on reducing the
Trypansosoma cruzi and Leishmania
infantum burden in platelets. Vox
Sang 2008; 95:290
17 Castro E, Gonzalez LM, Rubio JM,
et al.: The efficacy of the ultraviolet C
pathogen inactivation system in the
reduction of Babesia divergens in
pooled buffy coat platelets. Transfu-
sion 2014; 54:2207–16
18 GravemannU,HandkeW,LambrechtB,
et al.: Ultraviolet C light efficiently inac-
tivates nonenveloped hepatitis A virus
and feline calicivirus in platelet concen-
trates. Transfusion 2018; 58:2669–74
19 Gravemann U, Handke W, Muller TH,
et al.: Bacterial inactivation of platelet
concentrates with the THERAFLEX
UV-Platelets pathogen inactivation
system. Transfusion 2019; 59:1324–32
20 Seghatchian J, Struff WG, Reichenberg
S: Main properties of the THERAFLEX
MB-plasma system for pathogen
reduction. Transf Med Hemother 2011;
38:55–64
21 Spearman C: The method of "right and
wrong cases" ("constant stimuli")
without Gauss’s formulae. Br J Psychol
1908; 2:277–82
22 Kaerber G: Beitrag zur kollektiven
Behandlung pharmakologischer Rei-
henversuche. Naunyn Schmiedebergs
Arch Exp Pathol Pharmakol 1931;
162:480–3
23 Agafonov AP, Gus’kov AA, Ternovoi
VA, et al.: Primary characterization of
SARS coronavirus strain Frankfurt 1.
Dokl Biol Sci 2004; 394:58–60
24 Olschlager S, Gabriel M, Schmidt-
Chanasit J, et al.: Complete sequence
and phylogenetic characterisation of
Crimean-Congo hemorrhagic fever
virus from Afghanistan. J Clin Virol
2011; 50:90–2
25 Wild TF: Henipaviruses: a new family
of emerging Paramyxoviruses. Pathol
Biol (Paris) 2009; 57:188–96
26 Woolhouse ME, Haydon DT, Antia R:
Emerging pathogens: the epidemiology
and evolution of species jumps. Trends
Ecol Evol 2005; 20:238–44
27 de Wit E, van Doremalen N, Falzarano
D, et al.: SARS and MERS: recent
insights into emerging coronaviruses.
Nat Rev Microbiol 2016; 14:523–34
28 Dunstan RA, Seed CR, Keller AJ:
Emerging viral threats to the Aus-
tralian blood supply. Aust N Z J Pub-
lic Health 2008; 32:354–60
29 Bente DA, Forrester NL, Watts DM,
et al.: Crimean-Congo hemorrhagic
fever: history, epidemiology, patho-
genesis, clinical syndrome and genetic
diversity. Antiviral Res 2013;
100:159–89
30 Conger NG, Paolino KM, Osborn EC,
et al.: Health care response to CCHF in
US soldier and nosocomial transmis-
sion to health care providers, Ger-
many, 2009. Emerg Infect Dis 2015;
21:23–31
31 Sharma V, Kaushik S, Kumar R, et al.:
Emerging trends of Nipah virus: A
review. Rev Med Virol 2019; 29:e2010
32 Ang BSP, Lim TCC, Wang L: Nipah
virus infection. J Clin Microbiol
201856(6):e01875-17
33 Nikolay B, Salje H, Hossain MJ, et al.:
Transmission of nipah virus - 14 years
of investigations in Bangladesh. N
Engl J Med 2019; 380:1804–14
34 McCullough J, Alter HJ, Ness PM:
Interpretation of pathogen load in
relationship to infectivity and patho-
gen reduction efficacy. Transfusion
2019; 59:1132–46
©2020 International Society of Blood Transfusion
Vox Sanguinis (2020)
6M. Eickmann et al.
